单项选择题 The man in charge of a ship is（）.He is responsible for the ship ,her cargo and the safety of the crew.

单项选择题 （）is placed in the front of the ship under the water,which eases berthing or ma-noeuvering sideways at slow speed.

单项选择题 （）is a roud-shaped underwater part in the front of the ship.The purpose is to cre-ate less friction with water so that the ship moves more easily.