【单选题】
In a （） boiler the water flows through the inside of the tubes while the hot gases pass around the outside.
A、water-tube
B、fire-tube
C、exhaust gas
D、none of the above
查看正确答案
A、natural circulation of the water in the water tube boiler is better than that in the fire tube boiler B、for the same output the water tube boiler will carry less mass of water compared with the fire tube boiler C、the water tube boiler will cost shorter time for steam raising D、the water tube boiler require lower skill in operating and maintaining
