Question 418044
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Hi
Note:(NORMSINV(0.005) = -2.57583 as one example of a resource.
As to the critical z-values for a two-tailed hypothesis test:   A
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	a	a/2	crtical regions	
90%	10	5%	z <-1.645	z >+1.645
95%	5	2.50%	z <-1.96	z >+1.96
98%	2	1%	z <-2.33	z >+2.33
99%	1	0.50%	z<-2.575	z >+2.575