<samp id="tlxh9"><label id="tlxh9"></label></samp>

<ol id="tlxh9"><small id="tlxh9"></small></ol>

<ol id="tlxh9"><optgroup id="tlxh9"></optgroup></ol>

<fieldset id="tlxh9"></fieldset>

單項選擇題

Which of the following pumps are self-priming, and can deal with liquid from a level below the pump? （）
(1) reciprocating
(2) rotary
(3) centrifugal

A.（1）only
B.（1）and（2）
C.（1），（2）and（3）
D.（2）and（3）

你可能感興趣的試題

單項選擇題

A positive displacement pump is that where the volume of the pump chamber is alternately （） to draw the liquid in and then （） to force the liquid out.

A.increased；decreased
B.decreased；increased
C.decreased；decreased
D.increased；increased

單項選擇題

The pressure head of a water pump is given in the unit of （）.

A.kg
B.MPa
C.mH20
D.None of the above

感谢您访问我们的网站，您可能还对以下资源感兴趣：

国产黄色视屏

视频一区二区无码制服师生国产三级香港三级人妇国产码一区二区在线观看国产伦精品一区二区三区免费观看