李四是具有林木种子生产经营许可证的种子生产经营者，并以书面委托张三生产、代销其林木种子,那么张三的生产经营许可证应当由谁核发（）

Shutdown price（or point，or rule） 停业价格（或停业点、停业原则）

翻译：With Average or With Particular Average（WA or WPA）（）

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。

简述种子生产学的主要内容和任务。

老农王某在自家地里种了一亩白菜,肥料、种子等费用共花去他300元,对王某来说,他也可以选择种烤烟,预期总收益3000元,则他种植白菜的机会成本为

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。