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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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考题
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单选题In a diesel engine jacket water cooler, with seawater cooling the fresh water, the（）A
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Any time the vessel moves from water of one density into waters of a different densityB
Prior to getting underway when the vessel is floating in fresh or brackish waterC
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increase the amount of cooling water to the condenserB
decrease the amount of cooling water to the condenserC
add more refrigerant to the systemD
remove some refrigerant from the system
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