单选题The rate of heat transfer in a water-tube auxiliary boiler can be increased by （）.Aoperating the boiler at less than normal water levelBinstalling fins on the firesides of water-tubesCincreasing the amount of excess air to the burnersDtreating the boiler water with chemical oxygen scavengers
单选题
The rate of heat transfer in a water-tube auxiliary boiler can be increased by （）.
A
operating the boiler at less than normal water level
B
installing fins on the firesides of water-tubes
C
increasing the amount of excess air to the burners
D
treating the boiler water with chemical oxygen scavengers
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