In a certain binomial distribution, = 0.20 and n = 30. In using the normal approximation,

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 x = 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).