单项选择题
A.day
B.week
C.month
D.year
单项选择题 It is the responsibility of the Master or person in charge of a ship to ensure that().
单项选择题 In each inflatable liferaft,what equipment is provided to make quick,emergency,temporary repairs to large holes in the raft? ()
单项选择题 In an emergency,the electro-hydraulic steering units can be directly controlled by the().