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單項(xiàng)選擇題

Too much air in the furnace of an oil-fired boiler would be indicated by （）.

A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame

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單項(xiàng)選擇題

The feed water to the boiler will comprise （）.

A.condensate
B.a small amount of make-up feed
C.A and B
D.None of the above

單項(xiàng)選擇題

Proper combustion in a boiler would be indicated by （）.

A.yellowish flame
B.golden yellow flame
C.white flame
D.brilliant white flame