—When is Women's Day?
—It's _______. [ ]
A. May 1st
B. June 1st
C. July 1st
D. March 8th
D
对于小于50平方米的一下的中心机房用电量不小于(),50平方米以上用电量不小于40KW。
A.35KW
B.25KW
C.20KW
D.40KW
石膏类包埋材料的主要成分是()
A.SiO2
B.二氧化硅
C.磷酸盐
D.石英
E.硬质石膏