单项选择题 The starting air bottle should be pumped up to maximum pressure by the （） before start of the engine.

单项选择题 The process during which liquid containing a reasonable amount of sensible heat at a particular pressure immediately changes into steam after admitted to a chamber at a lower pressure is called （）.

单项选择题 When distilling salt water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.