同度量因素时期选择的一般原则是：数量指标综合指数的同度量因素时期固定在报告期，质量指标综合指数的同度量因素时期固定在基期。（）

什么是同度量因素？同度量因素在统计指数中有何作用？

简述布尔算符（OR）的作用。

OR指令的作用是: 。( )

同度量因素在综合指数中的作用有( )。

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, 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。