(a) in a recent survey, 80% of the community in town A favored building a police substation in their neighborhood. if 15 citizens are chosen, what is the mean number favoring the substation?

Hint: This is a binomial experiment (and we do not need to use the binomial probability formula

B) in a recent survey, 77% of the community in town B favored building a police substation in their neighborhood. If 14 citizens are chosen, find the probability that exactly 5 of them favor the building of the police substation.