A test is made of H0: = 18 versus H1: u 18.A sample of size n = 53

isdrawn,and x=20.The population standard deviation is = 8

.

(a) Compute the value of the test statistic z. (b) Is H0 rejected at the = 0.05 level? (c) Is H0 rejected at the = 0.01 level?

H1	Critical Values for =0.05	Critical Values for =0.01
Left-tailed
Right-tailed
Two-tailed	and	and