97免费在线观看视频,亚洲综合自拍网,黄色毛片免费观看,热久久综合网,免费看日产一区二区三区 狠狠操av,久久久涩涩涩,在线精品免费视频,人人插天天干,久久91精品国产91久久

單項(xiàng)選擇題

The second stage feed-water temperature and shell absolute pressure in a multistage, flash type, distilling plant is ()

A.higher than the first stage feed-water temperature and absolute shell pressure
B.lower than the first stage feed-water temperature and absolute shell pressure
C.the same as the first stage feed-water temperature and absolute shell pressure
D.not related to the feed-water temperature and absolute shell pressure

微信掃碼免費(fèi)搜題