单项选择题
Our ship has not been to shipyard for a long time, the fouling on the ship’s hull greatly decreases her（）.
A.resistance B.weight C.speed D.displacement
单项选择题 Radar is not only to obtain（）,but also to measure their distance away from you.
单项选择题 The anchor was then（）and the siren sounded.
单项选择题 Are there many（）and warehouses in the port?
