<li id="8iqub"></li>

單項選擇題

Low pressure air is usually taken through （） or pressure regulators to a low pressure reservoir supplying a ring main through driers.

A.globe valves
B.butterfly valves
C.gate valves
D.reducing valves

你可能感興趣的試題

單項選擇題

A number of biological sewage treatment plants are in use at sea but nearly all work on what is called the extended aeration processBasically the consists of oxygenating the liquor by bubbling air through itAccording to the above two sentences, the word "this" means （）.

A.a sewage treatment plant
B.the extended aeration process
C.the liquor
D.the bubbling air

單項選擇題

Explosions do occur （） caused by the ignition of oil or vapour gaining access from compressors or defective engine starting valves.

A.in boiler drums
B.in refrigerating plants
C.in starting air pipes
D.in air coolers

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