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單項(xiàng)選擇題

Which lubricating oil additive is used in diesel engines to reduce the tendency for sludge and varnish to form on the engine parts?（）

A.Flash point improvers
B.Pour point improvers
C.Inhibitors
D.Foam suppressors

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單項(xiàng)選擇題

Which of the following characteristic of lube oil helps to reduce the amount of deposits in the piston ring belt during the combustion process in a diesel engine?（）

A.Low viscosity index
B.Low carbon forming tendencies
C.High film strength
D.High non-corrosive qualities

單項(xiàng)選擇題

A diesel engine exposed to widely varying ambient temperatures should use to a lubricating oil with （）

A.a high viscosity index
B.a low viscosity index
C.neutralize acids
D.resist oxidation at high temperatures

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