According to a survey, college student make an average of 77 calls per week on their cell phone. Moreover 80% of the students surveyed indicated that their parents pay their cell phone expenses.
a. If you select a student at random what is the probability that he or she makes 10 calls in a day?
b. If you select a random sample of 10 students, what is the probability of at least 2 have parents pay their cell phone expenses?