单选题When distilling sea water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.Ato decrease scale formationBfor better cooling effectCfor more economical purposeDto raise vacuum
单选题
When distilling sea water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.
A
to decrease scale formation
B
for better cooling effect
C
for more economical purpose
D
to raise vacuum
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