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單項選擇題

（） is a source of power by which the diesel engine may operate.

A.Water energy
B.Electrical energy
C.Chemical energy
D.Heat energy

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單項選擇題

（） is a precaution which contributes to avoiding trouble under normal operating conditions.

A.Constant inspection
B.Keeping constant load
C.Remaining constant temperature
D.varying speed

單項選擇題

（） are mounted on and bolted to the bed-plate cross girders.

A.The crankshaft
B.The crankcase
C.The guide-ways
D.The frames