单项选择题
A.secure the lifeboat in the davits when in the stowed position
B.bring the lifeboat close alongside the rail in the embarkation position
C.give the occupants a safety line when the boat is being lowered from the embarkation level
D.reduce the swinging of the lifeboat at the embarkation level
单项选择题 Forty-five fathoms is marked on the anchor chain by（）.
单项选择题 Forces within a drilling unit have caused a difference between the starboard and port drafts. This difference is（）.
单项选择题 For the purpose of training and drills，if reasonable and practicable，rescue boats on an OSV must be launched with their assigned crew（）.