单项选择题
When using the lifeboat compass，you must be careful to（）.
A.set it on the centerline of the boat B.apply the correction for compass error C.keep metal objects away from it D.All of the above
单项选择题 When transferring survivors from an enclosed lifeboat to a rescue vessel，personnel on board the boat should（）.
单项选择题 When operating the air supply system in a covered lifeboat the（）.
单项选择题 When launching an open lifeboat by falls，the boathooks should be（）.
