7 航海技术

7    航海技术 7.2  锚泊与靠离泊作业 551．Your vessel has anchored in a channel known to have strong tidal currents． To check your position you take a round of bearings，one of which is a range in line． One hour later the bearing on the lights in range opens up． This indicates the ship is ______. A.  swinging                                    B.  dredging her anchor C.  taking bearings of the lights                      D.  taking distances of the lights KEY:  A 552．Your 15-meter tug is underway and crossing a deep and narrow channel. A large container vessel is off your port bow on a steady bearing. Which statement is TRUE concerning this situation? ______. A.  You should maintain course and speed. B.  The container vessel is the stand-on as it is the larger vessel. C.  You are not to impede the safe passage of the container vessel in the channel. D.  None of the above KEY:  C 553．A Danforth lightweight anchor does NOT hold well in which type of bottom? A.  Mud      B.  Grass      C.  Sand      D.  Clay KEY:  B 554．A mooring line is described as being 6x24，1-3/4 inch wire rope. What do the above numbers refer to? A.  Strands，yarns，circumference            B.  Strands，wires，diameter C.  Wires，yarns，diameter                D.  Strands，circumference，wires KEY:  B 555．A mooring system that results in a spread system without anchor buoys is called a ______. A.  permanent chasing system                B.  wire rope mooring system C.  shepherd's crook mooring system          D.  spring buoy mooring system KEY:  A 556．A vessel brought alongside should be fended off the towing vessel by ______. A.  crew members using their arms    B.  crew members using the strong muscles of their legs C.  fenders        D.  No fending is necessary due to the rugged construction of most towing vessels. KEY:  C 557．A vessel is wind rode when it is ______. A.  at anchor and heading into the wind        B.  backing into the wind C.  carrying lee rudder                      D.  necessary to apply a leeway correction to the course KEY:  A 558．A vessel moored with two anchors，sometimes，at an exposed roadstead to ______. A.  aid turning the ship                    B.  obtain a fine bearing C.  increase ship swings to wind or tide        D.  lighten the stress of anchor chains KEY:  D 559．After casting off moorings at a mooring buoy in calm weather，you should ______. A.  go full ahead on the engine(s) B.  back away a few lengths to clear the buoy and then go ahead on the engines C.  go half ahead on the engines and put the rudder hard right D.  go half ahead on the engines and pass upstream of the buoy KEY:  B 560．An example of an anchor which has a stock is a ______. A.  Bruce anchor      B.  Dunn anchor        C.  Hook anchor          D.  LWT anchor KEY:  D 561．Anchoring and fishing in this area are ______. A.  danger            B.  dangerous          C.  dangerously          D.  dangering KEY:  B 562．Before letting the anchor go，you should check that the ______. A.  chain is clear                          B.  anchor is clear of obstructions C.  wildcat is disengaged                    D.  All of the above KEY:  D 563．By paying out more anchor cable，you ______. A.  decrease the holding power of your anchor  B.  decrease the swing of your vessel while at anchor C.  increase the holding power of your anchor  D.  increase the possibility that your vessel will drag anchor KEY:  C 564．Chafing gear should be placed ______. A.  at all wearing points of mooring lines      B.  at the bitter ends of all standing rigging C.  around running rigging                  D.  on wire rope only KEY:  A 565．Consideration should be given in planning for the mooring orientation in a new location so that in adverse weather a crane is available to off-load the supply vessel on what side of the unit? ______. A.  Weather side      B.  Leeward side        C.  Upwind side        D.  Crosswind side KEY:  B 566．During a storm，the chance of fatigue failure of a mooring line will increase as ______. A.  vessel motions increase  B.  mooring tensions decrease  C.  KG increases  D.  KG decreases KEY:  A 567．Galvanizing would not be suitable for protecting wire rope which is used for ______. A.  cargo runners    B.  mooring wires        C.  shrouds          D.  stays KEY:  A 568．In a combination chain and wire rope mooring system，the anchor chain is deployed at the anchor end of the line to ______. A.  increase fatigue life of the system            B.  reduce the time to retrieve the line C.  increase the holding power                  D.  reduce the catenary KEY:  C 569．In a crossing situation，a vessel fishing must keep out of the way of a vessel which is ______. A.  under sail  B.  towing  C.  restricted in her ability to maneuver  D.  engaged in pilotage duty KEY:  C 570．Installing tandem anchors on the same mooring line is referred to as ______. A.  doubling      B.  pretensioning      C.  piggybacking      D.  paralleling KEY:  C 571．It is sometimes necessary to moor bow and stern to two mooring buoys in order to ______. A.  avoid any swing in a restricted space          B.  shelter the ship from strong winds C.  prevent from touching with other vessels        D.  make a convenience of cargo discharging KEY:  A 572．Leg penetration to depths which require pullout forces greater than that which can be supplied by the buoyancy of the hull may exist in ______. A.  soft mud              B.  sand            C.  silt            D.  soft to firm clays KEY:  D 573．Mooring with two bow anchors has which major advantage over anchoring with one bow anchor? ______. A.  The vessel will not reverse direction in a tidal current. B.  The radius of the vessel's swing will be shortened. C.  A mooring approach may be made from any direction. D.  The vessel will not swing with a change in wind. KEY:  B 574．On a single-screw vessel，when coming port side to a pier and being set off the pier，you should ______. A.  swing wide and approach the pier so as to land starboard side to B.  approach the pier on a parallel course at reduced speed C.  make your approach at a greater angle than in calm weather D.  point the vessel's head well up into the slip and decrease your speed KEY:  C 575．Owing to the big draught of the ship，she has to go alongside by the time of ______. A.  spring tide        B.  flood tide        C.  ebb tide          D.  slack water KEY:  A 576．Pilotage in this country is {compulsory}． A.  free of charge    B.  important        C.  required        D.  unnecessary KEY:  C 577．The anchor chain should be kept moderately taut during a Mediterranean moor to ______. A.  facilitate speed of recovery during the weighing process B.  indicate the anchor's location to passing or mooring ships C.  prevent damage to the stern in the event of a headwind D.  provide a steady platform for the gangway between the fantail and pier KEY:  C 578．The anchors should be dropped well out from the pier while at a Mediterranean moor to ______. A.  eliminate navigational hazards by allowing the chain to lie along the harbor bottom B.  increase the anchor's reliability by providing a large catenary in the chain C.  permit the ship to maneuver in the stream while weighing anchors D.  prevent damage to the stern caused by swinging against the pier in the approach KEY:  C 579．The best method of determining if a vessel is dragging anchor is to note ______. A.  the amount of line paid out                    B.  how much the vessel sheers while at anchor C.  any change in the tautness of the anchor chain    D.  changes in bearings of fixed objects onshore KEY:  D 580．The holding capabilities of an anchor are determined PRIMARILY by the ______. A. design of the anchor  B. weight of the anchor  C. scope of the anchor chain  D. size of the vessel KEY:  C 581．The holding power of an anchor at a given scope of cable increases when the ______. A.  amount of chain lying along the bottom increases    B.  length of the catenary is reduced C.  mooring line tension is increased      D.  amount of chain lying along the bottom decreases KEY:  A 582．The length of chain between the anchor and the end of the pendant line is called the ______. A.  pigtail chain        B.  thrash chain        C.  crown chain          D.  wear chain KEY:  C 583．The lockmaster has given you permission to tie off on the lower guide wall to wait your turn to lock through. What should you be most concerned with? A.  A downbound vessel B.  An upbound vessel C.  Current reaction when the lock chamber is being emptied D.  Current reaction when the lock chamber is being filled KEY:  C 584．The most doubtful and unpredictable factor in a mooring system is the ______. A.  ability of the anchors to hold in a seabed            B.  anchor chain catenary length C.  variability of the fairlead                        D.  angle of the flukes KEY:  A 585．The Pilotage-quarantine anchorage，______ between Damen Dao and Qingshan Dao，is defined by the lines ______ the given points． A. situated／connected    B. situated／connecting    C. situating／connected    D. situating／connecting KEY:  B 586．The purpose of the stripping bar on an anchor windlass is to ______. A.  clean off any mud that may have accumulated on the chain      B.  engage or disengage the wildcat C.  fairlead the chain from the hawse pipe to the wildcat    D.  prevent the chain from fouling the wildcat KEY:  D 587．The safest device used to secure the end of the pendant wire when it is initially passed to the anchor handling vessel is a ______. A.  pelican hook      B.  hydraulic deck stopper      C.  connecting link        D.  shackle KEY:  B 588．The ship ______ on a low rock was broken in two by the waves． A. that had been driven    B. had been driven      C. have been driven  D. which to have been driven KEY:  A 589．The ship is moored ______ buoys. A.  of              B.  on                C.  alongside            D.  to KEY:  D 590．There are two classes of vessels which，to the extent necessary to carry out their work，do not have to comply with the rule regarding traffic separation schemes. One of these is a vessel ______. A.  engaged in fishing in a traffic lane          B.  servicing a submarine cable C.  towing another                          D.  engaged on pilotage duty KEY:  B 591．To ensure the best results during the Mediterranean moor，the chains should ______. A.  be crossed around the bow                  B.  tend out at right angles to the bow C.  tend aft 60°from each bow                  D.  tend forward 30°on either bow KEY:  D 592．Vessels lying afloat at buoys for more than 24 hours should use anchor chain for ______ and insurance wire for ______. A.  bow mooring／stern line                      B.  forward spring／after spring C.  forward breast rope／forward spring            D.  slip rope／stern line KEY:  A 593．Wale shores would be used when drydocking a vessel with ______. A.  tumble home      B.  excessive deadrise      C.  excessive trim      D.  a list KEY:  B 594．We took usual steps：sounding the depth，reversing and stopping engine，paying out anchor and 60 fathoms of chain cable in the depth of 12 fathoms．The operation above is ______. A.  berthing        B.  searching              C.  anchoring        D.  picking up pilot KEY:  C 595．What could cause a significant difference between actual chain tension and the tension measured by the tensiometer? A.  The type of anchor and mooring line being used B.  The type of bottom in which the ship is anchored C.  A significant difference between air and water temperature D.  The chain contacting a chock or fairlead between the tensiometer and the lower swivel fairlead KEY:  D 596．What is the purpose of the intermediate spring? A.  Serves as a backup for the main tow hawser in case of failure. B.  Provides weight and flexibility to the total tow makeup. C.  Lengthens the main tow hawser to keep the tow in step. D.  Distributes the towing load. KEY:  B 597．What type of stopper would you use on a nylon mooring line? A.  Chain              B.  Nylon            C.  Manila              D.  Wire KEY:  B 598．When anchored，increasing the scope of the anchor chain normally serves to ______. A.  prevent fouling of the anchor            B.  decrease swing of the vessel C.  prevent dragging of the anchor            D.  reduce strain on the windlass KEY:  C 599．When anchoring a vessel under normal conditions，which scope of chain is recommended? A.  Four times the depth of water                B.  Two and one-half times the depth of water C.  Five to seven times the depth of water        D.  Fifteen times the depth of water KEY:  C 600．When anchoring，good practice requires 5 to 7 fathoms of chain for each fathom of depth. In deep water you should use ______. A.  the same ratio                            B.  more chain for each fathom of depth C.  less chain for each fathom of depth            D.  two anchors with the same ratio of chain KEY:  C 7.3 沿海与大洋航行 601．You are to ______ the convoy at 1745 hours． A.  get          B.  take          C.  have          D.  join KEY:  D 602．Which statement about a tunnel bow thruster is TRUE? A.  It provides lateral control without affecting headway. B.  It is fully effective at speeds up to about six knots. C.  It can be used to slow the ship in addition to backing down. D.  It will allow you to hold a position when the current is from astern. KEY: 603．______ is prohibited in this area． A.  Anchor          B.  Anchoring        C.  Anchored          D.  Being anchored KEY:  B 604．A reaching course is one in which the wind ______. A.  comes directly over the bow                    B.  comes directly over the stern C.  comes over an area extending from broad on the bow to the quarter    D.  has no effect on the vessel KEY:  C 605．A single vessel being towed alongside shall exhibit ______. A.  one all-round white light                    B.  sidelights and a sternlight C.  only the outboard sidelight and a sternlight      D.  a masthead light，sidelights，and a sternlight KEY:  B 606．A tow astern is veering from side to side on its towline. The best way of controlling the action is to ______. A.  trim the tow by the bow                    B.  trim the tow by the stern C.  list the tow to windward                    D.  adjust the length of the towing bridle KEY:  B 607．A tow that is properly aligned to pass through a narrow opening between two bridge piers is ______. A.  on course            B.  headed fair          C.  holding on              D.  in shape KEY:  D 608．A towing vessel and her tow are severely restricted in their ability to change course. When making way，the towing vessel will show ONLY ______. A. the masthead lights for a towing vessel    B. the lights for a vessel restricted in her ability to maneuver C. sidelights，stern light，and towing light          D. All of the above. KEY:  D 609．A towing vessel is tripped when ______. A.  it is overtaken by the tow B.  it is pulled sideways by the tow C.  the weight of the towing hawser causes loss of maneuverability D.  the propeller is fouled by the towing hawser KEY:  B 610．A tug would NOT assist a ship to steer if the tug is made up to the large vessel ______. A.  by a tow line ahead of the vessel            B.  forward on either bow of the vessel C.  approximately amidships of the vessel      D.  on the vessel's quarter KEY:  C 611．A vessel is proceeding from a very cold climate to a warm climate．With a cargo of non-hygroscopic nature，which of the following is correct？ ______. A.  There is danger of heavy cargo sweat if outside air is introduced by ventilation． B.  Danger of the ship sweat exists．Constant and vigorous ventilation is required． C.  There is little danger of ship's sweat；slight possibility of cargo sweat． D.  The possibility of any ship or cargo sweat is remote KEY:  A 612．A vessel must proceed at a safe speed ______. A.  in restricted visibility    B.  in congested waters      C.  during darkness      D.  at all times KEY:  D 613．A wedge of water building up between the bow and nearer bank which forces the bow out and away describes ______. A.  bank cushion          B.  bank suction            C.  combined effect        D.  bend effect KEY:  A 614．An ocean tow is sinking in deep water. Attempts to sever the towing hawser are unsuccessful. Which action should now be taken? A. Abandon the towing vessel.                    B. Radio for emergency assistance. C. Slip the towline and allow it to run off the drum.  D. Secure all watertight openings on the towing vessel. KEY:  C 615．An overtaking situation would be one in which one vessel is approaching another from more than how many degrees abaft the beam? A.  0°          B.  10°          C.  22.5°            D.  None of the above KEY:  C 616．As you approach Kate Aubrey Bar Light (mile 788 AHP)，yoursearchlight will show what type of marking at the light? A.  Green square    B.  Red and green banded square    C.  Green triangle      D.  Green diamond KEY:  A 617．As you approach Shreves cut-off you see Red River LandingGage (302.4 AHP) which reads 4.2 feet. Which of thefollowing statements is TRUE? A.  This reading is at the same elevation as the 6.2 ft. mark on the gage at Head of Passes. B.  A vessel drawing 8 ft would be able to pass over the sill at Old River Lock C.  This reading is 6.4 feet below the Low Water Reference Plane. D.  A vessel drawing 7 ft. would be able to pass through the locks at Lower Old River. KEY:  C 618．Every vessel shall at all times proceed at a safe speed so that she can ______. A.  take proper and effective action to avoid collision B.  be stopped within a distance appropriate to the prevailing circumstances and conditions． C.  neither A nor B D.  both A and B． KEY:  D 619．Every vessel shall proceed at a safe speed ______ the prevailing circumstances and conditions． A.  adapted to      B.  used by      C.  liable to      D.  adaptation to． KEY:  A 620．Every vessel should at all times proceed at a safe speed. Safe speed is defined as that speed where ______. A.  you can stop within your visibility range  B.  you can take proper and effective action to avoid collision C.  you are traveling slower than surrounding vessels      D.  no wake comes from your vessel KEY:  B 621．How does an icebreaker normally free a ship which has become beset while navigating independently? A.  By backing down the track and cutting out ice on either bow B.  By approaching from the stern and crossing ahead at an angle of 20°to 30°to the beset ship's course C.  By overtaking the beset ship，running ahead and then backing down the track to the beset vessel D.  By approaching the vessel from astern and towing the beset vessel stern first KEY:  B 622．If a ship is proceeding towards the magnetic equator，the uncorrected deviation due to permanent magnetism ______. A.  increases            B.  remains the same C.  decreases            D.  is unimportant and may be neglected KEY:  C 623．If the PSCO from general impressions or observations on board has _______for believing that the ship，its equipment or its crew do not substantially meet the requirements，the PSCO should proceed to a more detailed inspection. A.  clean report      B.  serious deficiencies      C.  clear ground      D.  detention report KEY:  C 624．If you do NOT understand the course or intention of an approaching vessel you should sound ______. A.  one short blast                    B.  one prolonged blast   C.  not less than five short blasts          D.  not less than five prolonged blasts KEY:  C 625．In stopping distances of vessels，head reach can best be described as the ______. A.  difference between the vessel's speed through the water at any instant and the new speed ordered on the telegraph B.  distance the vessel has actually run through the water since a change of speed was ordered C.  distance the vessel will run between taking action to stop her and being stationary in the water D.  speed at which a vessel should proceed to ensure that she will run a predetermined distance，once her engines have been stopped KEY:  C 626．It is an ______ condition precedent in every voyage charter-party that the ship shall proceed on the voyage without departure from her proper course． A.  implemented              B.  implied          C.  impossible          D.  improper KEY:  B 627．Large vessel leaving． Keep clear ______ approach channel． A.  off              B.  reach                C.  from                    D.  of KEY:  D 628．Mainly east 3 or 4 partly cloudy to overcast occasional rain ______ slowly south moderate or good． A.  spreading            B.  proceeding          C.  bounding for          D.  going to KEY:  A 279．Mariners are reminded that they should proceed in the general direction indicated by the arrows or，if ______ a lane，they should do so as nearly as practicable at right angles to it． A.  cross            B.  crossing          C.  crossed            D.  crosses KEY:  B 630．Mariners proceeding across the main routes are ______ to do so at as wide an angle as practicable． A.  recommended        B.  reported          C.  applied      D.  complied KEY:  A 631．Mariners proceeding across the main routes are recommended to do so at ______. A.  as wide an angle as practicable        B.  as wide an angle so practicable C.  like wide an angle as practicable        D.  like wide as angle so practicable KEY:  A 632．On a gnomonic chart，a great circle track between Los Angeles and Brisbane will appear as a ______. A.  loxodromic curve            B.  curved line concave to the equator C.  straight line                  D.  spiral approaching the poles as a limit KEY:  C 633．Risk of collision exists when an approaching vessel has a(n) ______. A.  generally steady bearing and decreasing range  B.  generally steady range and increasing bearing C.  increasing range and bearing                D.  decreasing bearing only KEY:  A 634．RYC8/TKS PLSPROCEED PEAKIS MEET/PLT SHIFT W/ANCH FOR/QTINE THEN/TO E/ANCH FOR/SUPPLY. This telex indicates that ______. A.  the vessel will anchor at eastern anchorage and take supply at the western anchorage B.  the vessel will anchor at western anchorage and take supply at the eastern anchorage C.  the vessel will anchor at eastern anchorage and take supply there D.  the vessel will anchor at western anchorage and take supply there KEY:  B 635．Safe speed is defined as that speed where ______. A.  you can stop within your visibility range B.  the vessel is not subject to vibrations C.  you are traveling slower than surrounding vessels D.  you can take proper and effective action to avoid collision KEY:  D 636．Some of these shoals have been disproved and are not charted． Nevertheless mariners should ______ with particular caution in this area． A.  go            B.  proceed            C.  move              D.  remove KEY:  B 637．Sometimes a tropical storm moves so slowly that a vessel，if astern of it，can ______ it． A.  cross          B.  approach          C.  proceed near        D.  run into KEY:  D 638．The approach to the roads and harbor from the ______ entails no difficulty． A.  eastern        B.  easterly            C.  eastward            D.  eastwards KEY:  C 639．The court has the power to ______ the time for commencing arbitration proceedings if it is of the opinion that in the circumstances of the case undue hardship would otherwise be caused． A.  pretend        B.  extend            C.  contend              D.  intend KEY:  B 640．The Light List shows a lighted aid to navigation on the left bank. This means that the light can be seen on the starboard side of a vessel ______. A.  ascending the river  B.  descending the river  C.  crossing the river  D.  proceeding towards sea KEY:  A 641．The rules state that vessels may depart from the requirements of the Rules when ______. A.  there are no other vessels around            B.  operating in a narrow channel C.  the Master enters it in the ship's log          D.  necessary to avoid immediate danger KEY:  D 642．The term of Landfall means ______. A.  Land first sighted when vessel approaching from seaward B.  Land last sighted when vessel leaving from a port C.  in sight of one another when vessel underway D.  in sight of an island during a ship on her voyage KEY:  A 643．Two vessels are approaching each other near head on. What action should be taken to avoid collision? _____. A.  The first vessel to sight the other should give way. B.  The vessel making the slower speed should give way. C.  Both vessels should alter course to starboard. D.  Both vessels should alter course to port. KEY:  C 644．When approaching Block Island Sound from Long Island Sound，you will enter waters governed by the International Rules of the Road when you ______. A.  pass through The Race B.  cross the territorial sea boundary C.  exit Block Island Sound to the east or south D.  None of the above，as Long Island Sound is governed by the International Rules of the Road KEY:  A 645．When attempting an upstream landing while pushing empty barges ahead in a hard onshore wind，the approach is best made ______. A.  with bow out，stern in                          B.  with bow in，stern out C.  parallel to the dock，as close in as possible        D.  parallel to the dock，as far out as possible KEY:  A 646．When steering a tow downstream around the shape of a sand bar，and staying on the proper side of the buoys，an operator should be cautious of ______. A.  eddies under the bar        B.  swift current under the bar causing loss of control C.  cross-currents pushing the tow away from the bar    D.  cross-currents pushing the tow into the bar KEY:  A 647．When towing astern，increased catenary will ______. A.  increase control of the tow                    B.  prevent the towing vessel from going in irons C.  make the towing vessel less maneuverable        D.  reduce shock stress on the towing hawser KEY:  D 648．When towing in an open seaway，it is important to use a towing line ______. A.  made only of wire rope，due to possible weather conditions B.  that will have the tow on a crest while your vessel is in a trough C.  that will have the tow on a crest while your vessel is on a crest D.  with little dip to gain maximum control of the tow KEY:  C 649．When underway and proceeding ahead，as the speed increases，the pivot point tends to ______. A.  move aft        B.  move forward            C.  move lower        D.  remain stationary KEY:  B 650．When using the anchor to steady the bow while approaching a dock you must be aware of the fact that ____. A.  the vessel will tend to take a large sheer towards the side where the anchor is down B.  steering control is ineffective in trying to turn to the side opposite to that of the anchor being used C.  the anchor cable must never lead under the hull D.  using an offshore anchor decreases the chances of the anchor holding KEY:  D 7.6  海上避碰规则 651．A sailing vessel is overtaking a steam vessel in a fairway on International waters，so as to pass on the steam vessel's port side． The sailing vessel is the ______. A.  privileged vessel and would sound two short blasts． B.  burdened vessel and would sound two prolonged blasts followed by two short blasts． C.  burdened vessel and would sound no whistle signal． D.  privileged vessel and would sound no whistle signal． KEY:  B 652．A stand-on vessel in a crossing situation is allowed to take action when ______. A.  on a collision course B.  the vessels will pass within one mile C.  it becomes apparent to her that the give-way vessel is not taking appropriate action D.  the relative speed of the vessels indicates collision in less than six minutes KEY:  C 653．A towing vessel becomes tripped while towing on a hawser astern. What factor is MOST important when assessing the risk of capsizing? A.  Length of the towline                        B.  Height of the towline connection C.  Longitudinal position of the towline connection    D.  Direction of opposing force KEY:  B 654．A vessel constrained by her draught shall，when risk of collision with another vessel in a crossing or head-on situation exists，______. A.  apply the relevant Steering and Sailing Rules as a power-driven vessel B.  apply the relevant Steering and Sailing Rules as a Sailing vessel C.  apply the relevant Steering and Sailing Rules as a vessel not under command D.  apply the relevant Steering and Sailing Rules as a vessel engaged in a towing operation． KEY:  A 655．A vessel engaged in fishing underway sounds the same fog signal as a ______. A.  power-driven vessel stopped and making no way through the water    B.  vessel being towed C.  vessel restricted in her ability to maneuver at anchor            D.  sailing vessel at anchor KEY:  C 656．A vessel has sustained damage in a collision with another vessel. It is necessary to have a Seaworthy Certificate before the vessel sails. Who will issue this certificate? A.  American Consul                      B.  Classification Society C.  Captain of the Port                      D.  Officer in Charge，Marine Inspection KEY:  B 657．A vessel is approaching from dead ahead． Both of her sidelights are visible and her range lights are in line． Which of the following could you do first？ ______. A.  Sound one blast of the whistle．          B.  Alter course to starboard． C.  Construct a radar plot．                  D.  Sound the danger signal． KEY:  B 658．A vessel is in sight of another vessel when ______. A.  she can be observed by radar              B.  she can be observed visually from the other vessel C.  she can be plotted on radar well enough to determine her heading  D.  her fog signal can be heard KEY:  B 659．A vessel is in sight of another vessel when she ______. A.  can be observed by radar      B.  has determined that risk of collision exists C.  is sounding a fog signal which can be heard on the other vessel D.  can be observed visually from the other vessel KEY:  D 660．A vessel restricted in her ability to maneuver is one which ______. A.  through some exceptional circumstance is unable to maneuver as required by the Rules B.  from the nature of her work is unable to maneuver as required by the Rules C.  due to adverse weather conditions is unable to maneuver as required by the Rules D.  has lost steering and is unable to maneuver KEY:  B 661．All of the following are practices of good seamanship EXCEPT ______. A.  When meeting，altering course to the left to increase sea room． B.  Maintaining an alert radar watch in reduced visibility． C.  Showing a flare-up light to attract attention when you are not under command． D.  Maintaining a proper lookout from sunrise to sunset． KEY:  A 662．All of the following constitute special circumstances EXCEPT ______. A.  Three vessels meeting so as to cross each other's course． B.  A vessel meeting a vessel that is backing out of a slip． C.  An overtaking situation that has reached in extremis． D.  A vessel fishing with nets meeting a sailing vessel． KEY:  D 663．Any alteration of course and／or speed to avoid collision shall，if the circumstances of the case admit，______ to another vessel observing visually or by radar． A.  be large enough to be readily apparent B.  be a succession of small alterations C.  be with due regard to the power and speed of the vessel D.  leave sufficient room for the other vessel to take action． KEY:  A 664．Any vessel ______ any other shall keep out of the way of the vessel ______. A.  overtaking／overtaken                      B.  being overtake／being overtaken C.  overtaking／being overtaken                D.  being overtaking／overtaken． KEY:  C 665．If it becomes necessary for a stand-on vessel to take action to avoid collision，she shall NOT，if possible_. A.  decrease speed                          B.  increase speed C.  turn to port for a vessel on her own port side  D.  turn to starboard for a vessel on her own port side KEY:  C 666．If there is any doubt as to the proper operation of a radar，which statement is TRUE? ______. A. Only a radar expert can determine if the radar is operating. B. All radars have indicator lights and alarms to signal improper operation. C. A radar range compared to the actual range of a known object can be used to check the operation of theradar. D. The radar resolution detector must be energized to check the radar. KEY:  C 667．If there is sufficient sea room，alteration of ______ may be the most effective action to avoid close-quarters situation． A.  speed and course        B.  speed alone        C.  course alone      D.  speed or course． KEY:  C 668．If your vessel is underway in fog and you hear one prolonged and three short blasts，this is a ______. A.  vessel not under command                B.  sailing vessel C.  vessel being towed (manned)              D.  vessel being towed (unmanned) KEY:  C 669．In a crossing situation on open waters，a sailing vessel shall keep out of the way of all the following vessels EXCEPT a vessel ______. A.  not under command                B.  restricted in her ability to maneuver C.  engaged in towing                D.  fishing KEY:  C 670．In determining if risk of collision exists the following considerations shall be among ______. A.  these taken into calculation            B.  those taking into account C.  that taken into account                D.  those taken into account． KEY:  D 671．In determining safe speed，the Rules list all of the following as factors which must be taken into account EXCEPT the ______. A.  limitations of radar equipment            B.  presence of background lights at night C.  maximum horsepower of your vessel      D.  maneuverability of your vessel KEY:  C 672．In fog you observe your radar and determine that risk of collision exists with a vessel which is 2 miles off your port bow. You should ______. A.  stop your engines            B.  sound the danger signal at two-minute intervals C.  hold course and speed until the other vessel is sighted    D.  take avoiding action as soon as possible KEY:  D 673．In order for a vessel to be engaged in fishing she must be ______. A.  underway                      B.  using gear which extends more than 50 meters outboard C.  using a seine of some type          D.  using gear which restricts her maneuverability KEY:  D 674．In order to maintain speed while changing course from a close reach to a broad reach，the sails should be ___. A.  lowered        B.  reefed            C.  hauled in        D.  eased out KEY:  D 675．In reduced visibility，you hear two prolonged blasts of a whistle. This signal is sounded by a ______. A.  power-driven vessel dead in the water                B.  sailing vessel on the port tack C.  vessel not under command                          D.  vessel fishing with nets KEY:  A 676．In restricted visibility a towed vessel must sound a fog signal when it is ______. A.  the last vessel in the tow                      B.  the last vessel in the tow and it is carrying a crew C.  manned，regardless of its position in the tow      D.  None of the above are correct KEY:  B 677．In restricted visibility the speed of a vessel without operational radar may be ______ enable effective avoiding action to be taken on sighting another ship． A.  too low to          B.  too high to            C.  too high for            D.  too low for． KEY:  A 678．In the daytime，you see a large sailing vessel on the beam. You know that she is also propelled by machinery if she shows ______. A.  a basket          B.  a black ball          C.  a black cone          D.  two black cones KEY:  C 679．It has often been stressed in the Courts that the look-out man should，preferably，be stationed forward，unless weather conditions make this ______. A.  possible          B.  practicable            C.  impossible            D.  probably． KEY:  C 680．On open waters，a power-driven vessel shall keep out of the way of a ______. A.  vessel on her port side that is crossing her course        B.  vessel that is overtaking her C.  seaplane on the water                              D.  sailing vessel KEY:  D 681．On open waters，a vessel fishing is in a crossing situation with a vessel sailing located on the fishing vessel's starboard side. Which vessel is the stand-on vessel? ______. A. The fishing vessel because it is to port of the sailing vessel.  B. The fishing vessel because it is fishing. C. The sailing vessel because it is to starboard of the fishing vessel.  D. The sailing vessel because it is sailing. KEY:  B 682．Power-driven vessels must keep out of the way of sailing vessels except ______. A.  in a crossing situation    B.  when they are making more speed than the power-driven vessel C.  when the sailing vessel is overtaking        D.  on the Inland Waters of the United States KEY:  C 683．Risk of collision is considered to exist if ______. A.  four vessels are nearby            B.  a vessel has a steady bearing at a constant range C.  there is any doubt that a risk of collision exists    D.  a special circumstance situation is apparent KEY:  C 684．Sailing vessels are stand-on over power-driven vessels except ______. A.  in a crossing situation                    B.  in a meeting situation C.  when they are the overtaking vessel          D.  on the inland waters of the PR China. KEY:  C 685．The effectiveness of the action shall be carefully checked until the other vessel is finally ______. A.  past            B.  clear            C.  past or clear              D.  past and clear． KEY:  D 686．The risk of collision shall be deemed to exist if the compass bearing of an approaching vessel ______. A.  did not appreciably change              B.  does not appreciably change C.  do not appreciably change              D.  not appreciably change KEY:  B 687．The rules require that a stand-on vessel SHALL take action to avoid collision when she determines that ____. A.  risk of collision exists              B.  the other vessel will cross ahead of her C.  the other vessel is not taking appropriate action D.  collision cannot be avoided by the give-way vessel's maneuver alone KEY:  D 688．The Rules state that certain factors are to be taken into account when determining safe speed. One of the factors is the ______. A.  radio communications that are available                  B.  maximum speed of your vessel C.  temperature                                        D.  current KEY:  D 689．The Rules state that certain factors are to be taken into account when determining safe speed. Those factors include ______. A.  state of wind，sea，and current，and the proximity of navigational hazards B.  maximum attainable speed of your vessel C.  temperature D.  aids to navigation that are available KEY:  A 690．The steering and sailing rules for vessels in restricted visibility apply to vessels ______. A.  in sight of one another in fog                B.  navigating in or near an area of restricted visibility C.  only if they are showing special purpose lights        D.  only if they have operational radar KEY:  B 691．The term power-driven vessel means ______ in these Rules． A.  any sailing vessel with propelling machinery B.  any vessel propelled by machinery C.  any sailing vessel with or without machinery for propelling D.  any sailing vessel with propelling machinery not in use． KEY:  B 692．The term restricted visibility，when used in the Rules，refers to ______. A.  situations when you can see vessels on radar that you cannot see visually B.  visibility of less than half a mile C.  any condition where visibility is restricted D.  visibility where you cannot see shore KEY:  C 693．The wind is ESE，and a sailing vessel is steering NW. Which fog signal should she sound? A.  One blast at one-minute intervals    B.  One blast at two-minute intervals C.  Two blasts at one-minute intervals  D.  One prolonged and two short blasts at two-minute intervals KEY:  D 694．Under International Rules ______. A.  all vessels must carry an after range light． B.  vessels less than 50 meters in length need not carry an after range light． C.  vessels stopped dead in the water should turn off their range lights． D.  vessels over 20 meters in length must carry both range lights from sunset to sunrise． KEY:  B 695．Underway vessels shall at all time maintain a proper look-out ______. A.  by sight and hearing only                    B.  by all available means besides sight and hearing C.  by all available means except sight and hearing    D.  by none of above means． KEY:  B 696．Vessel constrained by her draught is ______. A.  a non-power driven vessel            B.  a sailing vessel C.  a power driven vessel                D.  a power driven vessel or a non-power driven vessel． KEY:  C 697．Vessel underway means that a vessel is ______. A.  on the way  B.  at anchor  C.  made fast to a terminal  D.  moving against water． KEY:  D 698．Vessels shall be deemed to be in sight of one another only when one ______ from the other． A.  can be observed visually            B.  can be observed by radar C.  can be located on the radar          D.  can be heard． KEY:  A 699．What determines if a vessel is restricted in her ability to maneuver? ______. A.  Whether or not all of the vessel's control equipment is in working order B.  The vessel's draft in relation to the available depth of water C.  Whether the nature of the vessel's work limits maneuverability required by the Rules D.  Whether or not the vessel is the give-way vessel in a meeting situation KEY:  C 700．When a pushing vessel and a vessel being pushed are rigidly connected in a composite unit，they shall be regarded as ______. A.  a tugboat                    B.  a sailing vessel C.  a power-driven vessel          D.  a vessel propelled by machinery and under sail KEY:  C 7.8  地文航海 701．Leeway is the ______. A.  difference between the true course and the compass course B.  momentum of a vessel after her engines have been stopped C.  lateral movement of a vessel downwind of her intended course D.  displacement of a vessel multiplied by her speed KEY:  C 702．______ is the process by which the position of the vessel at any moment is found by applying the last well-determined position to the run that has been made since，using for this purpose the ship's course and the distance being those indicated by log． A.  dead reckoning      B.  dead weight      C.  dead slow ahead      D.  dead slow astern KEY:  A 703．______ means the curve on the earth's surface which cuts all the meridians at the same angle． A.  Great Circle        B.  Position Line        C.  Rhumb line        D.  True Bearing KEY:  C 704．A bold reef is a reef ______. A.  with part of it extending above the water        B.  that can be detected by water turbulence C.  that drops off sharply                        D.  perpendicular to the current KEY:  B 705．A buoy having red and green horizontal bands would have a light characteristic of ______. A.  interrupted quick flashing                B.  composite group flashing C.  Morse (A)                            D.  quick flashing KEY:  B 706．A buoy marking a wreck will show a(n) ______. A.  white light FL (2) and a topmark of 2 black spheres    B.  occulting green light and may be lettered C.  yellow light and will be numbered    D.  continuous quick white light and may be numbered KEY:  A 707．A buoy with a composite group-flashing light indicates a(n) ______. A.  anchorage area      B.  fish net area      C.  bifurcation      D.  dredging area KEY:  C 708．A buoy，being a shape of cylinder and with red group flashing，shows that it is ______. A.  left-side buoy    B.  right-side buoy      C.  a buoy of safety  D.  a buoy of danger KEY:  A 709．A cardinal mark showing an uninterrupted quick-flashing white light indicates the deepest water in the area is on the ______. A. north side of the mark  B. west side of the mark  C. east side of the mark  D. south side of the mark KEY:  A 710．A dead reckoning (DR) plot ______. A.  ignores the effect of surface currents            B.  is most useful when in sight of land C.  must be plotted using magnetic courses          D.  may be started at an assumed position KEY:  A 711．A dead reckoning (DR) plot ______. A.  must utilize magnetic courses            B.  must take set and drift into account C.  should be replotted hourly                D.  should be started each time the vessel's position is fixed KEY:  D 712．A fairly accurate estimation of a ship's position can be calculated by a technique known as ______. A.  dead reckoning      B.  Pilotage      C.  great circle sailing      D.  geographic navigation KEY:  A 713．A large navigational buoy (LNB) is painted ______. A.  red                                    B.  yellow C.  with red and white vertical stripes            D.  with a distinct color and pattern unique to each buoy KEY:  A 714．A line connecting all possible positions of your vessel at any given time is a ______. A.  longitude line      B.  latitude line          C.  line of position          D.  fix KEY:  C 715．A line of position is ______. A.  a line connecting two charted objects B.  a line on some point of which the vessel may be presumed to be located C.  the position of your vessel D.  not used in a running fix KEY:  B 716．A position obtained by applying only your vessel's course and speed to a known position is a ______. A.  dead-reckoning position        B.  fix          C.  probable position        D.  running fix KEY:  A 717．A position obtained by crossing lines of position taken at different times and advanced to a common time is a(n) ______. A.  running fix        B.  dead-reckoning position          C.  fix          D.  estimated position KEY:  A 718．A position that is obtained by applying estimated current and wind to your vessel's course and speed is a(n) _. A.  dead reckoning position      B.  estimated position      C.  fix      D.  None of the above KEY:  B 719．A position that is obtained by using two or more intersecting lines of position，taken at nearly the same time，is a(n) ______. A.  estimated position      B.  fix      C.  running fix          D.  dead-reckoning position KEY:  B 720．A relative bearing is always measured from ______. A.  true north        B.  magnetic north          C.  the vessel's beam        D.  the vessel's head KEY:  D 721．A single line of position combined with a dead-reckoning position results in a(n) ______. A.  running fix        B.  fix          C.  estimated position          D.  assumed position KEY:  C 722．A vessel's position should be plotted using bearings of ______. A.  buoys close at hand              B.  fixed known objects on shore C.  buoys at a distance              D.  All of the above KEY:  B 723．At the magnetic equator there is no induced magnetism in the vertical soft iron because ______. A.  the lines of force cross the equator on a 0°-180°alignment B.  the quadrantal error is 0° C.  there is no vertical component of the Earth's magnetic field D.  the intercardinal headings have less than 1°error KEY:  C 724．In plotting a running fix，how many fixed objects are needed to take your lines of position from? A.  Three          B.  Two            C.  One            D.  None KEY:  C 725．Lighted white and orange buoys must show which color light? A.  Orange          B.  White            C.  Red            D.  Alternating yellow and white KEY:  B 726．Preferred channel buoys indicate the preferred channel to transit by ______. A.  odd or even numbers                                B.  the color of their top band C.  the location of the buoy in the channel junction          D.  the buoy's light rhythms KEY:  B 727．Restricted areas at locks and dams are indicated by ______. A.  flashing red lights upstream and fixed red lights downstream    B.  yellow unlighted buoys C.  signs and/or flashing red lights        D.  red daymarks upstream and green daymarks downstream KEY:  C 728．The luminous range of a light takes into account the ______. A.  glare from background lighting                    B.  existing visibility conditions C.  elevation of the light                            D.  observer's height of eye KEY:  B 729．The maximum distance at which a light may be seen under the existing visibility conditions is called ______. A.  nominal range    B.  luminous range    C.  charted range      D.  geographic range KEY:  B 730．The nominal range of a light may be accurately defined as the maximum distance at which a light may be seen ______. A.  under existing visibility conditions          B.  under perfect visibility C.  with ten miles visibility                  D.  with fifteen miles visibility KEY:  C 731．The period of a lighted aid to navigation refers to the ______. A.  date of construction or establishment          B.  length of time between flashes of the light C.  time required for the longest flash of each cycle  D.  time required for the light to complete each cycle KEY:  D 732．The positions and characteristics of lights and buoys shown within the port area are ______. A.  untrue        B.  impossible          C.  suspectful              D.  unimportant KEY:  A 733．The shortest distance between any two points on earth defines a ______. A.  small circle      B.  great circle        C.  rhumb line            D.  hyperbola KEY:  B 734．There are a number of buoys {in the vicinity}． A.  nearby          B.  in view          C.  visible                D.  far from KEY:  A 735．There is sufficient anchorage for ______ at all time around the No．1 buoy and for smaller vessels around the No．4 buoy． A.  deep laded vessels  B.  deeply load vessels  C.  deep loading vessels  D.  deeply loaded vessels KEY:  D 736．This is ______ where we shall anchor． A.  the light-house      B.  the anchorage      C.  the pilot station      D.  the light-buoy KEY:  B 737．Two navigational hazards are located near to each other，but each is marked by an individual cardinal buoyage system. The buoys of one cardinal system may be identified from the other system by ______. A.  the differing light colors B.  one system having odd numbers while the other system has even numbers C.  one system using horizontal bands while the other system uses vertical stripes D.  the difference in the periods of the light KEY:  D 738．Uncharted lights，fog signals and radar beacon transmissions may be ______ near the station． A.  encountered            B.  met            C.  contacted              D.  seen KEY:  A 739．Under the IALA - A Buoyage System，a buoy used as a port hand mark would not show which light characteristic? A.  Isophase      B.  Quick flashing        C.  Long flashing      D.  Group Flashing (2 + 1) KEY:  D 740．What describes an accurate position that is NOT based on any prior position? A.  Dead-reckoning position    B.  Estimated position    C.  Fix    D.  Running fix KEY:  C 741．What indicates a dual purpose buoy? A.  Red buoy with a horizontal yellow band B.  Red and white vertically-striped buoy with a vertical yellow stripe C.  Red and white vertically-striped buoy with a red spherical topmark D.  Green buoy with a yellow square KEY:  D 742．What is the light characteristic of a lighted，preferred-channel buoy? A. Group flashing  B. Composite group flashing  C. Interrupted quick flashing  D. Fixed and flashing KEY:  B 743．What is the major advantage of high altitude observations? A.  Errors due to unusual parallax are eliminated. B.  The same body can be used for a fix from observations separated by several minutes. C.  The declination is the only information needed from the almanac. D.  The semidiameter correction of the sextant altitude is eliminated. KEY:  B 744．When a buoy marks a channel bifurcation，the preferred channel is NOT indicated by ______. A.  the shape of an unlighted buoy      B.  the light color of a lighted buoy C.  the color of the topmost band        D.  whether the number is odd or even KEY:  D 745．When approaching a preferred-channel buoy，the best channel is NOT indicated by the ______. A.  light characteristic                    B.  color of the uppermost band C.  shape of an unlighted buoy            D.  color of the light KEY:  A 746．When entering a channel from seaward，the numbers on buoys ______. A.  are the same as their Light List number  B.  are marked in 6 inch figures with retroreflective material C.  increase with the even numbers to starboard      D.  decrease with the odd numbers to starboard KEY:  C 747．When entering from seaward，a buoy displaying a single-flashing red light would indicate ______. A.  a junction with the preferred channel to the left      B.  a sharp turn in the channel to the right C.  the starboard side of the channel                D.  a wreck to be left on the vessel's port side KEY:  C 748．When making landfall at night，you can determine if a light is a major light or an offshore buoy by ______. A.  the intensity of the light B.  checking the period and characteristics against the Light List C.  the color，because the buoy will have only a red or a green light D.  Any of the above can be used to identify the light. KEY:  B 749．When navigating a vessel，you ______. A.  can always rely on a buoy to be on station B.  can always rely on a buoy to show proper light characteristics C.  should assume a wreck buoy is directly over the wreck D.  should never rely on a floating aid to maintain its exact position KEY:  D 750．When using a buoy as an aid to navigation which of the following should be considered? A.  The buoy should be considered to always be in the charted location. B.  If the light is flashing，the buoy should be considered to be in the charted location. C.  The buoy may not be in the charted position. D.  The buoy should be considered to be in the charted position if it has been freshly painted. KEY:  C 7.9  潮汐与涌浪 801．A stream of water immediately surrounding a moving vessel's hull，flowing in the same direction as the vessel is known as ______. A.  directional current    B.  forward current      C.  propeller current    D.  wake current KEY:  D 802．A structure，usually made of stone，or cement pilings，which extends from the bank at approximately right angles to the current is called a ______. A.  dike          B.  revetment            C.  cutoff            D.  crib KEY:  A 803．Current refers to the ______. A.  vertical movement of the water            B.  horizontal movement of the water C.  density changes in the water              D.  None of the above KEY:  B 804．Currents are ______ in rate and direction． A.  vary          B.  variable              C.  variably              D.  variability KEY:  B 805．Generally speaking，a ship steaming across the North Pacific from Japan to Seattle is likely to experience __. A.  adverse currents for practically the entire crossing B.  favorable currents for practically the entire crossing C.  favorable currents in the summer months and adverse currents in the winter months D.  variable currents having no significant effect on the total steaming time KEY:  B 806．In mid-ocean，the characteristics of a wave are determined by three factors. What is NOT one of these factors? A.  Effect of the moon's gravity        B.  Fetch C.  Wind velocity                  D.  Length of time a wind has been blowing KEY:  A 807．In which month will the equatorial counter current be strongest? A.  January          B.  April            C.  August          D.  October KEY:  C 808．Neap tides occur ______. A.  at the start of spring，when the Sun is nearly over the equator B.  only when the Sun and Moon are on the same sides of the Earth and are nearly in line C.  when the Sun and Moon are at approximately 90°to each other，as seen from the Earth D.  when the Sun，Moon，and Earth are nearly in line，regardless of alignment order KEY:  C 809．Neap tides occur only ______. A.  at a new or full Moon                B.  when the Sun，Moon，and Earth are in line C.  at approximately 28-day intervals      D.  when the Moon is at quadrature KEY:  D 810．Neap tides occur when the ______. A.  Moon is in its first quarter and third quarter phases  B.  Sun and Moon are on opposite sides of the Earth C.  Moon's declination is maximum and opposite to that of the Sun  D.  Sun and Moon are in conjunction KEY:  A 811．One of the causes of ocean currents is density differences in the water. This is true because ______. A.  in an area of high density the water's surface is lower than in an area of low density B.  surface water flows from an area of high density to one of low density C.  the lesser the density gradient the freer the water is to move D.  it is the density differences that cause the currents to stay in the troughs KEY:  B 812．Priming of the tides occurs ______. A.  at times of new and full Moon B.  when the Earth，Moon，and Sun are lying approximately on the same line C.  when the Moon is between first quarter and full and between third quarter and new D.  when the Moon is between new and first quarter and between full and third quarter KEY:  D 813．River currents tend to ______. A.  pick up speed where the channel widens      B.  run slower in the center of the channel C.  hug the inside of a bend    D.  cause the greatest depth of water to be along the outside of a bend KEY:  D 814．Scouring is the result of ______. A.  interruption of the normal current flow by the footing      B.  elevating in mud-slide zones C.  penetrating rapidly through a hard crust into weaker soils D.  extracting legs from soils with high cohesion KEY:  A 815．Set of current is ______. A.  its velocity in knots            B.  direction from which it flows C.  estimated current              D.  direction toward which it flows KEY:  D 816．Spring tides are tides that ______. A.  have lows lower than normal and highs higher than normal  C.  are unpredictable B.  have lows higher than normal and highs lower than normal    D.  occur in the spring of the year KEY:  A 817．Spring tides occur ______. A.  at the start of spring，when the Sun is nearly over the equator B.  only when the Sun and Moon are on the same side of the Earth and nearly in line C.  when the Sun and Moon are at approximately 90°to each other as seen from the Earth D.  when the Sun，Moon，and Earth are nearly in line，in any order KEY:  D 818．Spring tides occur ______. A.  when the moon is new or full B.  when the moon and sun have declination of the same name C.  only when the moon and sun are on the same sides of the earth D.  at the beginning of spring when the sun is over the equator KEY:  A 819．Stand of the tide is that time when ______. A.  the vertical rise or fall of the tide has stopped    B.  slack water occurs C.  tidal current is at a maximum        D.  the actual depth of the water equals the charted depth KEY:  A 820．Swell is the rise and fall of the ocean's surface due to ______. A.  fetch      B.  distant winds        C.  local storms          D.  the pull of the moon KEY:  B 821．The Benguela Current flows in a ______. A.  SW'ly direction along the NW coast of Africa      B.  S'ly direction off the East Coast of Australia C.  NW'ly direction along the SW coast of Africa      D.  SW'ly direction along the SE coast of Greenland KEY:  C 822．The best time to work a boat into a slip is ______. A.  when the wind is against you                  B.  with the current setting against you C.  at slack water                              D.  with a cross current KEY:  C 823．The Brazil Current flows in which general direction? A.  Northwesterly      B.  Southwesterly        C.  Southerly        D.  Northerly KEY:  B 824．The current rates ______ excess of 2 kn may occur with prolonged strong winds． A.  by              B.  with                C.  on                D.  in KEY:  D 825．The difference between the heights of low and high tide is the ______. A.  period            B.  range              C.  distance          D.  depth KEY:  B 826．The easiest way to anchor a vessel in a current is to ______. A.  stem the current and make very slow headway when the anchor is dropped B.  stem the current and be falling aft very slowly when the anchor is dropped C.  stem the current and endeavor to make neither headway nor sternway when the anchor is dropped D.  stop all headway through the water and keep the current astern when the anchor is dropped KEY:  B 827．The Humboldt Current flows in which direction? A.  North                B.  South                  C.  East                D.  West KEY:  A 828．The interval of the average elapsed time from the meridian transit of the moon until the next high tide is called the ______. A.  harmonic constant      B.  establishment of the port    C.  half-tide level      D.  tide cycle KEY:  B 829．The movement of water away from the shore or downstream is called a(n) ______. A.  reversing current      B.  ebb current          C.  flood current          D.  slack current KEY:  B 830．The navigational term SET OF CURRENT means ______. A.  velocity of current in knots                  B.  direction from which the current flows C.  estimated current                          D.  direction toward which the current flows KEY:  D 831．The north equatorial current flows to the ______. A.  east          B.  northeast            C.  southwest              D.  west KEY:  D 832．The set of the current is the ______. A.  speed of the current at a particular time        B.  maximum speed of the current C.  direction from which the current flows          D.  direction in which the current flows KEY:  D 833．The set of the equatorial countercurrent is generally to the ______. A.  north            B.  east              C.  southwest                D.  northwest KEY:  B 834．The set of the ocean current is caused by ______. A.  density differences of the water                      B.  rotation of the earth C.  direction of primary circulation of air                D.  all of the above KEY:  D 835．The speed of an ocean current is dependent on ______. A.  the density of the water                            B.  the air temperature C.  the presence of a high pressure area near it            D.  underwater soil conditions KEY:  A 836．The steady current circling the globe at about 60°S is the ______. A.  Prevailing Westerly  B.  Sub-Polar Flow  C.  West Wind Drift  D.  Humboldt Current KEY:  C 837．The term flood current refers to that time when the water ______. A.  is flowing towards the land          B.  is moving towards the ocean C.  level is not changing                D.  level is rising because of heavy rains KEY:  A 838．The tide ____.It's 2 hours before low water，and ___your present position you will be aground at low water． A.  falls／in      B.  has been falling／on        C.  has fallen／at        D.  is falling／in KEY:  D 839．The tide is ______. A.  black            B.  setting          C.  being        D.  having KEY:  B 840．The two most effective generating forces of surface ocean currents are ______. A.  temperature and salinity differences in the water      B.  wind and density differences in the water C.  water depth and underwater topography        D.  rotation of the Earth and continental interference KEY:  B 841．The type of current which will have the greatest effect on the course made good for your vessel is ______. A.  one flowing in the same direction as your course steered B.  one flowing in the opposite direction as your course steered C.  one that flows at nearly right angles to your course steered D.  a rotary current in which the direction of current flow constantly changes KEY:  C 842．The velocity of a rotary tidal current will be decreased when the Moon is ______. A.  at apogee          B.  new            C.  full              D.  All of the above KEY:  A 843．The velocity of the current in large coastal harbors is ______. A.  predicted in Tidal Current Tables              B.  unpredictable C.  generally constant                          D.  generally too weak to be of concern KEY:  A 844．The velocity of the wind，its steady direction，and the amount of time it has blown determines a wind driven current's ______. A.  temperature          B.  density            C.  deflection          D.  speed KEY:  D 845．The West Wind Drift is located ______. A.  near 60°S              B.  on each side of the Equatorial Current C.  in the North Atlantic between Greenland and Europe        D.  in the South Pacific near 5°S KEY:  A 846．The winds with the greatest effect on the set，drift，and depth of the equatorial currents are the ______. A.  doldrums        B.  horse latitudes            C.  trade winds        D.  prevailing westerlies KEY:  C 847．Tide is ______ in direction ENE． A.  getting          B.  setting                  C.  being              D.  having KEY:  B 848．To make sure of getting the full advantage of a favorable current，you should reach an entrance or strait at what time in relation to the predicted time of the favorable current? A.  One hour after the predicted time                B.  At the predicted time C.  30 minutes before flood，one hour after an ebb    D.  30 minutes before the predicted time KEY:  D 849．Tropic tides are caused by the ______. A.  Moon being at its maximum declination            B.  Moon crossing the equator C.  Sun and Moon both being near 0°declination        D.  Moon being at perigee KEY:  A 850．Water may boil up around the stern of a vessel in a channel due to ______. A.  slack water when upbound  B.  shallow water  C.  a cross current  D.  a head current KEY:  B