在CDMA移动通信系统中，利用（）扇形定向天线把一个蜂窝小区划分成三个扇区，降低了相互干扰。

有些计算机病毒能隐藏它对计算机的文件或引导扇区的修改，当程序读这些文件或扇区时，这些文件或扇区表现的是未被修改的原貌，这种特性称为计算机病毒的（）

口服补液及时纠正脱水，应用ORS，说法正确的是（）

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.

位置区更新属于电路域的移动性管理；路由区更新属于（）域移动性管理。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

移动台在通话中如果收到了连续12个坏帧，移动台会（）

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。