几何学中，向量的两个重要属性是（）

职业道德可以调节礼仪主持人与受众之间的关系。

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。

对两个关系进行等值连接，在其运算结果的关系中，属性个数小于两个关系的属性个数之和。

举例说明设计师管理中的两个重要方面。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

对两个关系进行等值连接，在其运算结果的关系中，属性个数小于两个关系的属性个数之和。