决定砂石筛分试验每次试样用量的因素是()。
A.砂石材料的化学组成
B.砂石材料的公称粒径
C.砂石材料的含水率
D.筛分结果精度要求
参考答案:B
what their friendships are based upon, the important thing to remember is both of them are friendships.
A.Regardless that
B.Regardless of, that
C.Though, /
D.Despite, what
从一批产品中随机抽取100件进行质量检验,结果有5件不合格,则样本成数的抽样平均误差为0.689。