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?/2, (b) find the critical value t?/2, (c) state that neither the normal nor the t distribution applies.
- $91 \% ; \mathrm { n } = 45 ; \sigma$ is known; population appears to be very skewed.

A) $\mathrm { z } _ { \alpha / 2 } = 1.75$
B) $\mathrm { t } _ { \alpha / 2 } = 1.34$
C) $\mathrm { z } _ { \alpha / 2 } = 1.70$
D) $t _ { \alpha / 2 } = 1.645$