At present, one of the apartments in favor of the new airport ________ that it will going a lot jobs to the area.

A．is

B．are

C．will be

D．were

以煤气为例，可燃气体无焰燃烧时具有（）的特点。

A、烟火黑度大，辐射能力强。

B、要求煤气压力低，50-300mm水柱即可。

C、不易回火。

D、燃烧速度快，燃烧空间热强高。