A door-to-door salesperson visits thirteen potential customers each day, and each customer makes a purchase with probability 0.15. The salesperson receives a sales award on any day where at least five customers make a purchase that day. Assume that the salesperson visits different potential customers each day, and that each customer behaves independently of the other customers. A. Compute the mean and variance of the number of customers who make purchases in a given day. B. Compute the probability that no customer makes a purchase in a given day. C. Compute the probability that the salesperson receives a sales award tomorrow. D. Compute the probability that the salesperson receives a sales award fewer than three times in one month (you may assume there are 20 working days in a month). E. At the end of a work day, the salesperson realizes that they last received a sales award three days ago. What is the probability that they receive their next sales award within the next four working days from today? (b)