Which of the following statements represents the advantage of rotary pumps as compared to reciprocating pumps?（） The high discharge pressure of the rotary pumps permits a larger volume of fluid per unit time than the reciprocating pump。 Rotary pumps are capable of pumping more fluid than reciprocating pumps of the same weight。 Rotary pumps occupy only one-half the space of reciprocating pumps。 Rotary pumps eliminate discharge slippage of the pumped liquid, while this does not hold true for a reciprocating pum。
有（）以上叶轮的离心泵称为多级离心泵。 一级。 两级。 五级。 十级。
After abandoning a vessel，water that is consumed within the first 24 hours will（）. pass through the body with little absorbed by the system。 help to prevent fatigue。 quench thirst for only 2 hours。 help to prevent seasickne。
According to the Insurance Terms of PICC，All Risk covers（）. total and partial loss。 4／4 collision liability。 general average。 all of the above。
买卖进出口许可证，进出口原产地证明以及其他法律、行政法规规定的经营许可证或批准文件的，情节严重的，处5年以下有期徒刑或拘役，并处或者单处违法所得1倍以上5倍以下罚金。（）
柱塞泵依靠柱塞在缸内做往复运动来改变工作室的（）达到吸入和排出液体的目的。
