单项选择题
A.use the float-free method only
B.lower all boats
C.raise all boats
D.drill is over，secure all boats
单项选择题 When should you use distress flares and rockets?（）
单项选择题 When launching a lifeboat，the tricing pennants should be released（）.
单项选择题 When landing a lifeboat through heavy surf with a strong current running parallel to the beach (from right to left when facing from seaward) the recommended procedure is to（）.