管路流动中，对于直径为d的圆形过水断面，其水力半径为（）。

水在垂直管内由上向下流动,相距l的两断面间,测压管水头差h,则两断面间沿程水头损失h_f为( )

只有过水断面上各点流速相等的流动才是均匀流。（）

恒定均匀流过水断面上各点的测压管水头都相同。

杜比公式是适用于恒定非均匀渐变层流渗流，同一过水断面上各点的渗流流速都相等且等于v=kJ。（）

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.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

均匀流的同一过水断面上，各点流速相等。

在管道突然扩大处，总水头线下降，测压管水头线上升。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。