单项选择题
A.2.2~2.4 B.2.8~3.0 C.3.0~3.6 D.4.2~6.0
A.石灰砂浆 B.水泥砂浆 C.细石混凝土 D.混合砂浆
A.120mm B.180mm C.200mm D.250mm