单项选择题
A.Immediately
B.After one hour
C.Only when another vessel is in sight
D.Only after sunset
单项选择题 When hanging off drill pipe in emergency situations aboard a ship，the preferred location of the drill bit is（）.
单项选择题 When amendments are made to the Shipboard Oil Pollution Emergency Plan，the revisions must be submitted to the Coast Guard（）.
单项选择题 When a survival craft drill is held，the person in charge must insure that（）.