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單項(xiàng)選擇題

The water in an auxiliary boiler should be tested daily for （）.

A.dissolved oxygen
B.chlorides
C.sludge
D.dissolved nitrogen

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單項(xiàng)選擇題

A feed pump for an auxiliary boiler might lose suction if the （）.

A.boiler water level is low
B.feedwater is too hot
C.boiler steam demand is low
D.feedwater is too cold

單項(xiàng)選擇題

Fuel is admitted to a diesel engine cylinder through the （）.

A.intake valves
B.carburetor
C.exhaust ports
D.injector nozzles

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