A.one year
B.two years
C.four years
D.five years
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A.Ring type
B.Fork type
C.Spade type
D.Push on pull off type
A.anaerobic bacteria
B.aerobic bacteria
C.air bubbles
D.disinfection chemicals
A.the temperature and flow quantity of the exhaust gas from M.E
B.the quantity of steam demanded
C.the rotary speed and the cooling water temperature of main engine
D.efficiency of M.E turbocharger
A.purge lube oil from the liquid refrigerant
B.recover water purged from the system
C.separate foul gases from the receiver
D.purge non-condensable gases without losing refrigerant
A.Sub-cooled liquid
B.Sub-cooled vapor
C.Superheated vapor
D.Liquid
最新試題
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