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單項選擇題

The selection of a lubricating oil depends to a great extent on the operating conditions,（）.

A.the type of coolant
B.the design of the engine
C.the type of fuel to be burned
D.B and C

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單項選擇題

The sealing rings are in four parts and pressed together around the piston rods by means of （）.

A.nuts
B.bolts
C.coil springs
D.stuffing boxes

單項選擇題

The scavenging box is built of a number of sections provided with vertical flanges enabling them （） together to form two blocks.

A.being bolted
B.bolted
C.bolting
D.to be bolted

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