单项选择题
Which device is designed to automatically hold the load if power should fail to an electric winch?（）
A.Pneumatic brake
B.Electromagnetic brake
C.Hand brake
D.Motor controller
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相关考题
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单项选择题
When the pilot is embarked he or she（）.
A.relieves the officer of the watch
B.relieves the Master of his duties
C.is solely responsible for the safe navigation of the vessel
D.is a specialist hired for his or her local navigational knowledge -
单项选择题
When must the Master or person in charge of a ship log the position of load line marks in relation to the surface of the water in the logbook?（）
A.Once a day
B.At the change of every watch
C.Only when in fresh or brackish water
D.Prior to getting underway -
单项选择题
What is the purpose of the limit switch on gravity davits?（）
A.To cut off the power when the davits hit the track safety stops
B.To stop the davits from going too fast
C.To cut off the power when the davits are about 12 inches or more from the track safety stops
D.None of the above
