___ is known to all, China will be an _____ and powerful country in 20 or 30 years’time.

A．That; advancing

B．This; advanced

C．As; advanced

D．It; advancing

DCC装置中稳定塔压力是通过（）控制。

A、用热旁路

B、不凝气出装置控制阀

C、干气出装置

D、外方汽油量