透平机的氯气冷却器内，气相压力必须大于液相压力。
参考答案：对
如果a与b互为相反数；x与y互为倒数，则代数式|a+b|﹣2xy值为[ ]
A．0
B．﹣2
C．﹣1
D．无法确定
Zhengzhou was attacked by such a terrible sandstorm ________ few residents had ever experienced before.
A．which
B．as
C．where
D．that
