4.92 A food truck owner, Ayesha, sells each roll for €2.50. She finds that 70% of her customers prefer chicken rolls. Suppose she makes a random selection of 8customers. State at the outset what assumption she has made. a. Find the probability that at least 2 customers prefer chicken rolls. b. Find the probability that exactly 6 customers prefer chicken rolls. c. Find the mean and standard deviation of the num- ber of customers who prefer chicken rolls. d. Find the mean and standard deviation of the total number of chicken rolls she sells.