单项选择题
The circulation around a low pressure center in the Northern Hemisphere is（）.
A.counterclockwise B.variable C.clockwise D.anticyclonic
单项选择题 How long are you prohibited to consume alcohol prior to serving as a member of a watch?（）
单项选择题 It is dangerous for vessels without the operational radar（）the estuary.
单项选择题 Bales close to the deckhead should be covered to prevent（）.
