What Are the Mean and Standard Deviation for the Normal $\mu$

Multiple Choice

What are the mean and standard deviation for the normal approximation to the binomial distribution with n = 100 and p = .20?

A) $\mu$ = 50 and
$\sigma$ = 5
B) $\mu$ = 50 and
$\sigma$ = 4
C) $\mu$ = 20 and
$\sigma$ = 16
D) $\mu$ = 20 and
$\sigma$ = 4