无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

單項(xiàng)選擇題

The thermostatic valve has a throttling action, that is to say the valve can()

A.stop the refrigerant from flowing
B.force the refrigerant to flow
C.cause the refrigerant pressure to rise
D.cause the refrigerant pressure to fall

微信掃碼免費(fèi)搜題