人民警察的敬礼规范有哪些？
Under rotary pumps are the gear, （）, cam-and-piston and screw types. reciprocating。 diffuser。 turbine。 vane。
多媒体技术中的“媒体”是指磁盘、磁带、光盘、半导体存储器等。
The water level in the gauge glass when a boiler is operating is （） when the boiler is shut down. lower than。 higher than。 below。 equal to。
在评价互斥方案时，现值指数与净现值比较两者不一致，没有资本限量条件下，应以现值指数为准选择方案。（）
The damage to a vessel is over $25，000. Who must notify the nearest Coast Guard Marine Safety or Marine Inspection Office as soon as possible?（）
