单项选择题 In a vapor compression refrigeration the evaporating pressure is maintained constant by the action of the （）, which removes vapor from the evaporator at the same rate at which it is formed.

单项选择题 What is the function of thermostatic expansion valve in a compression refrigeration system?（）

单项选择题 In a compression refrigeration plant the hot, high pressure refrigerant gas is cooled by the sea water and becomes liquid in the （）.