水准尺圆水准器的检验，在距水准仪约50m处的尺垫上安置水准尺，安平水准仪后，使水准尺的中线或边缘与望远镜中的竖丝重合，此时若水准尺的圆水准器气泡（），则不需校正。

校正圆水准器，首先旋转脚螺旋使气泡中心向（）移动偏距的一半。

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.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

水准仪、经纬仪或全站仪的圆水准器轴与管水准器轴的几何关系为相互垂直。

水准仪水准轴平行于视准轴检验与校正时，应进行（）的检验与校正。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。