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單項選擇題

The internal part of boiler should be cleaned by yard if found （）.

A.scaled
B.worn
C.deformed
D.rested

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單項選擇題

At normal sea going, we use （） instead of donkey boiler.

A.a heater
B.a pre-heater
C.an exhaust gas boiler
D.the coal burning boiler

單項選擇題

The soot blowers are operating in the oil fuel boiler the air/fuel ratio must （） throughout the action, and blowers greased after use.

A.be increased
B.be decreased
C.remain constant
D.either be increased or remain constant