单项选择题
Vessels should be manned（）duly qualified officers and crew adequate（）ensure the safety of navigation.
A.by/to B.with/to C.with/for D.from/for
单项选择题 VHF radio is one of the very important navigational instruments on board,（）messages can be sent.
单项选择题 When（）,the provision of the bill of lading will be used as a basis for settlement.
单项选择题 When the（）is large, the ship is stiff; and when it is small, she is tender.
