A.a roomB.roomC.roomsD.the roomThere is plenty of（）at t……

单项选择题There is not（）depth of water around the area centered at the lighthouse.

A.ample
B.sufficient
C.enormous
D.incredible

单项选择题The vessel was drifted off from her（）due to strong wind.

A.course
B.track
C.direction
D.trend

单项选择题The use of the danger signal（）.

A.replaces directional signals
B.makes the other vessel the stand-on vessel
C.indicates doubt as to another vessels actions
D.is the same as a MAYDAY signal

单项选择题The two main types of load cells used in mooring tension gauges are（）.

A.distortion and compression
B.hydraulic and mechanical
C.magnetic and applied torque
D.frictionless and hydraulic

单项选择题The transmission of messages respecting the dangers specified is free（）cost to the ships concerned.

A.of
B.on
C.at
D.in