某一外加劑進(jìn)行檢測(cè),拌和25L,所測(cè)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(yàn)結(jié)果無(wú)效,應(yīng)重做
A.1.5min B.2min C.2.5min D.3min
A.50Ns±10N/s B.80Ns±10N/s C.2400N/s±200N/s D.2500N/s±250N/s