单项选择题
A.molecular fluid vibration
B.energy losses
C.wide pressure variations
D.mechanical damage to control valves
单项选择题 One function provided by a hydraulic accumulator is to（）
单项选择题 A reservoir, as used in hydraulic systems aboard ship, is used to store hydraulic oilAnother function is to（）
单项选择题 To prevent the unnecessary loading of an air conditioning system while maintaining the designed dry bulb temperature and relative humidity in an air conditioning system, you should （）