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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

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單項選擇題

Water evaporates or steam condenses at the saturation temperature, which depends upon the pressure, the higher the pressure （） the saturation temperature.

A.the more
B.the higher
C.the lower
D.the highest

單項選擇題

A （） boiler is an auxiliary boiler sometimes included in a steamships installation for supplying steam to auxiliaries in port.

A.monkey
B.donkey
C.waste heat
D.main

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