关于假设检验,下列说法正确的是()
A.一定要计算检验统计量
B.检验水准的符号为β
C.P可以事先确定
D.备择假设用Ho表示
E.假设检验是针对总体的特征进行
参考答案:E
点P(4,-3)关于原点对称的点P1在第______象限.
—Mr. Smith, why are you always asking me to do the difficult work?
—Because you _______ do such a thing and nobody else is fit for it.
A.would
B.should
C.can
D.may