单项选择题
A.3~5mm的水泥砂浆 B.5~10mm的水泥砂浆 C.3~5mm的水泥净浆 D.5~10mm的水泥净浆
A.20mm,15mm B.30mm,20mm C.30mm,25mm D.25mm,20mm
A.0.1% B.0.2% C.0.3% D.0.4%