Excessive scale formation in a distilling plant may result from （）.

A.refrigerant boiling out of solution from the lube oil
B.liquid refrigerant flooding the compressor and system
C.lube oil viscosity being reduced by refrigerant dilution
D.compressor suction pressure suddenly increasing

A.It is corrosive
B.It is odorless
C.It is visible as h blue fog
D.It has a distinctive taste

A.settling in a fuel tank
B.testing in a laboratory centrifuge
C.burning in a calorimeter
D.testing in a closed cup