单项选择题
A.excessive heat B.friction C.oxidation D.high pressure
In the closed cooling system, the water （）.A.is made to...
单项选择题In the closed cooling system, the water （）.
A.is made to circulate out of the system B.is made to circulate within the system C.is made circulate within the system D.is made circulate out of the system
If the temperature drops low enough, oil will not flow,...
单项选择题If the temperature drops low enough, oil will not flow, （） just tell us the temperature.
A.Hash point B.Viscosity C.Pour point D.Cetane number
The （） can tell us how much heat we can get from the bu...
单项选择题The （） can tell us how much heat we can get from the burning of an oil.
A.viscosity B.flash point C.cetane number D.calorific value
