高压给水泵平衡水室的压力应比入口压力高()MPA,如发现此压差增大时,应停泵检查。
A、0~0.15
B、0.05~0.2
C、0.2~0.3
D、0.3~0.5
参考答案:B
Not all the students would rather computer games than . [ ]
A. play, study
B. playing, studying
C. to play, to study
D. playing , study
简述均质的意义?