设石灰石中,杂质为3.57%,CaCO3占96.43%。则生石灰中CaO()%。。
A、91
B、92
C、93
D、94
参考答案:D
Judy _____ a stomachache, so she _____ eat anything for twenty-four hours. [ ]
A. has; should
B. have; should
C. has; shouldn't
D. haven't; shouldn't
可以正转或反转的皮带运输机布置形势是()。
A、水平
B、倾斜
C、凹弧