You must take good care of the drainage cock of the air control system. Because lead scale formed which might malfunctions the pilot control valve and other instruments.A.the temperatureB.the rustC.the pressureD.the humidity
You must take good care of the drainage cock of the air control system. Because lead scale formed which might malfunctions the pilot control valve and other instruments.
A.the temperature
B.the rust
C.the pressure
D.the humidity
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