In a certain binomial distribution, π = 0.20 and n = 30, In using the normal approximation,
a. What are the mean and standard deviation of the corresponding normal distribution?
b. If the number of "successes" among the 30 observations, determine the following:
P(x = 5), P(4 ≤ x ≤7), P(1 ≤ x ≤ 5), P(x ≥ 7).