A.non-toxic gas
B.Oxygen
C.Hydrogen
D.Helium
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A.equatorial area
B.polar regions
C.mid-latitudes
D.All of the above
A.makes no change at all
B.is somewhat lower than it would be for winds from a northern quadrant
C.is uncertain and may fluctuate by increasing and decreasing
D.is somewhat higher than it would be for winds from the northern quadrant
A.logs must be kept in an orderly manner
B.erasures are not allowed
C.it must identify the vessel's name and official number
D.All of the above
A.the Sailing Directions and the Coast Pilot
B.a weather fax
C.the Local Notice to Mariners
D.the Light List
A.a break-glass and pull-cable system
B.electrical controls on the bridge
C.a mechanical arm outside the vent duct
D.the heat of a fire melting the link
最新試題
General information on enroute weather and climate is found in（）.
How do you determine the weight of the vessel that is supported by the ground when a vessel has run aground?（）
How does a coast radio station communicating by HF radio normally identify itself?（）
How could lashing gear used aboard Ro-Ro vessels be stowed when not in use?（）
General requirements for a vessel’s radiotelephone station log are that（）.
How can you estimate the position of a tropical storm’s center?（）
How does the effect known as “bank suction” act on a single-screw vessel proceeding along a narrow channel?（）
How do the height and location of a tug’s towing bitts relate to the danger of tripping?（）
From your position you observe a rotating white and green light to the north. This light is most likely（）.
Horizontal subdivision decks forming watertight compartments in the columns of a semisubmersible ship increase the unit’s（）.