喷入高炉的煤粉在风口前燃烧放出的热量与煤的发热值相比是()。
A.高很多
B.相等
C.低很多
参考答案:C
In the old days, many poor people had no food ______ and no rooms______.
A.to eat, to live
B.to eat, to live in
C.eating, living
D.eating, living in
在大样本的情况下,检验H0:μ=μo,H1:μ>μo,则()成立时,可接受原假设。
A.实测显著性水平P值<显著性水平α
B.P值>α
C.Z<Z0
D.Z>Z0
E.Z>Zα/2