（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

When loading or discharging dry mud or cement，crew members should use goggles and（）.

Effects which are dutiable or subject to prohibitions or restrictions should be declared in （）.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

以下哪些情况会造成提示“Incorrect number or IP address”？（）

流体静力学基本方程式表明了静止流体内部压力变化的规律。

在粗糙水平面上静止的物体，受到的力有（）。

推出的铅球，不计空气作用力时，它受到的力有（）。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。