在Excel中，若A1单元格中的字串是：“计算机”，A2单元格的字串是“学院”，现希望在A3单元格中显示“计算机学院学生名册”，则应在A3单元格中键入公式（）。

（）称为空串；（）称为空白串。

普通计算机变成多媒体计算机要解决的关键技术是：视频音频信号的获取技术，（），视频音频数据的实时处理和特技，视频音频数据的输出技术。

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.

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。

计算机中常采用原码、反码、补码和移码表示数据，其中，±0编码相同的是 （ ） 。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。