According to CNN/USA Today poll appox. 70% of Americans believe the IRS abuses its power. Let X equal the number of people who believe the IRS abuses its power in a sample of n=25 Americans. Assuming that the poll results are still valid , find the probability that
a) X is at least 13
b) X is at most 11
c) x is equal to 12
d) give the mean, variance, and standard deviation of X