单项选择题
A.10% B.10%～20% C.20%～40% D.40%～70%
A.普通水泥 B.硅酸盐水泥 C.火山灰质水泥 D.矿碴水泥
A.20mm B.22mm C.25mm D.30mm
A.30%～38% B.20%～28% C.10%～18% D.40%～48%
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