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 （）.

（）are liable to be stoten, pilfered or may damaged due to improper handing or stowage.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

描述统计学是研究如何根据样本数据去推断通体数量特征的方法

统计学中，把描述总体特征的指标为参数，把描述样本特征称为（）。

统计推断是根据样本数据来推断总体的数量特征。( )

研究如何利用样本数据来推断总体特征的统计学分支称为（）。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。