（）, 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.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

物体受八个互不平行的力作用而平衡，其力多边形是________。

物体受三个互不平行的力作用而平衡，其力多边形是________。

物体受五个互不平行的力作用而平衡，其力多边形是________。

物体受四个互不平行的力作用而平衡，其力多边形是________。

物体受七个互不平行的力作用而平衡，其力多边形是________。

物体受六个互不平行的力作用而平衡，其力多边形是________。