单项选择题
A.掺用有机塑化剂的砂浆,不得少于2minB.掺用外加剂的砂浆,不得少于2minC.水泥砂浆,不得少于2minD.水泥粉煤灰砂浆,不得少于2min
A.7d B.10d C.14d D.15d
A.20±2℃,90% B.20±3℃,90% C.20±2℃,95% D.20±3℃,95%