单项选择题
When the ship in the condition of stand-by and engine trials, usually put the engine telegraph in the （） position.
A.stand by B.slow ahead C.slow astern D.B or C
单项选择题 One hour before sailing, the duty engineer and officer should check （）
单项选择题 When stand-by before sailing, the duty engineer and officer should check clock, engine telegraph and rudder, and then write it in the （）
单项选择题 （） is (are) not power supplied by main switchboard directly.
