A.4.8% B.4.9% C.5.0% D.結果無效,應重做
某一外加劑進行檢測,拌和25L,所測數(shù)據(jù)如下: 則該外加劑的減水率為()。
A.21.5% B.21.9% C.22.2% D.試驗結果無效,應重做
A.1.5min B.2min C.2.5min D.3min