Question 939173
 = CI	z = value
90%	z =1.645
92%	z = 1.751
95%	z = 1.96 ****is the critical value of z
98%	z = 2.326
99%	z = 2.576
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D. test stat z = 2.15 will reject hypothesis
(too far to the right to support it) see below
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For the normal distribution: Below:  z = 0, z = ± 1, z= ±2 , z= ±3 are plotted. 
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z = 2.15 outside of x = 1.96
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