单项选择题
A.above
B.below
C.equal to
D.None of the above
单项选择题 The function of （） in a refrigeration plant using Freon is to move moisture from all refrigeration system.
单项选择题 The boiling and condensation points of refrigerant mainly depend on the （） exerted upon it.
单项选择题 In a compression refrigeration plant the refrigerant is under low pressure in the （） and under high pressure in the （）.