The probability that a voter will believe a rumor about a politician is .3. If 20 voters

Question:

The probability that a voter will believe a rumor about a politician is .3. If 20 voters are told individually:
(a) Find the probability that none of the 20 believes the rumor.
(b) Find the probability that seven or more believe the rumor.
(c) Determine the mean and standard deviation of the number who believe the rumor.