4.(22 points) It is reported that about 65% internet users use Google as the search engine. In a sample of 30 internet users, let X denote the number of users of Google..

a.Identify the random variable X. (i.e.What is the distribution for random variable X)(3 points)

b.What is the expected number of users of Google in the sample?(3 points)

c.What is the probability that at most 20 of them will use Google?(5 points)

d.What is the probability that at least 10 of them will use Google?(5 points)

e.Would it be unusual if 9 or fewer use Google?(6 points)