主压缩机的工作状态为当总风压力低至()时随机启用一台。
A、700kPa
B、800kPa
C、850kPa
D、900kPa
参考答案:C
六月份用电量比五月份节约12%,是把______看作“1”,六月份用电量是五月份的______%.
根据上句完成下句,使两句意思表达基本相同。
1. Yesterday afternoon it rained heavily, so I borrowed an umbrella from Ed.
Yesterday afternoon it rained heavily, so Ed _____ _____ an umbrella.
2. Allan went to play football with his friends at once after he finished his homework.
_____ _____ _____ he finished his homework, Allan went to. play football with his friends.