（）, 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（）.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

简述电子现金的基本特性。

电子现金应具有的基本特性：

什么是电子现金？电子现金有哪些特性？

电子现金具备的基本特性有（）

电子现金系统具备四个基本特点，其中保证电子现金能不被轻易地复制或篡改，属于（）

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。