Do One of the Following, as Appropriate: (A) Find the Critical

Multiple Choice

Do one of the following, as appropriate: (a) Find the critical value ${ } ^ { Z } \alpha / 2$ , (b) find the critical value ${ } ^ { t } \alpha / 2$ 99%; n = 17; $\alpha$ is unknown; population appears to be normally distributed.

A) zσ/2 = 2.583
B) tσ/2 = 2.921
C) tσ/2 = 2.898
D) zσ/2 = 2.567