施用化肥“三看”原则是什么？

长期大量施用化肥的土壤，其pH值会（）

施用化肥可增加土壤中重金属的积累。

我国化肥的平均施用量是发达国家化肥安全施用上限的2倍，平均利用率仅40％左右。

ANB指令是（）指令，ORB是（）指令，与and、or指令不同。

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。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。