建筑物内热水供应系统，按照热水供应范围可以分为（）、集中热水供应系统和区域热水供应系统三类。
参考答案：局部热水供应系统
--Look! There is a long queue waiting for the bus. Shall we take a taxi?
--_______. It will save us a lot of time.
A．I didn’t get it.
B．I couldn’t agree.
C．So what?
D．That’s a good point.
sum的值为0，则result=sum==0 1:hum/sum的值为______。
