David Desreumaux, VP of Human Resources of American First Banks $\alpha$

Multiple Choice

David Desreumaux, VP of Human Resources of American First Banks (AFB) , is reviewing the employee training programs of AFB.Based on a recent census of personnel, David knows that the variance of teller training time in the southeast region is 8, and he wonders if the variance in the southwest region is the same number.His staff randomly selected personnel files for 15 tellers in the southwest region, and determined that their mean training time was 25 hours and that the standard deviation was 4 hours.Assume that teller training time is normally distributed.Using $\alpha$ = 0.10, the null hypothesis is ________.

A) $\mu$ = 25
B) $\sigma$ ² = 8
C) $\sigma$ ² = 4
D) $\sigma$ ² $\le$ 8
E) s² = 16