单项选择题
A.190mm x 190mm x 190mmB.190mm x 190mm x 90mmC.240mm x 115mm x 90mmD.240mm x 180mm x 115mm
A.15%以上B.38%C.45%D.40%
A.粉煤灰B.石灰膏C.砂子D.砂浆