6. Refer to Question 8 (d) of PartA, in which we let A denote the amount of time a randomly selected customer spends on hold with some insurance company. Suppose X follows a distribution with a mean of 8 hours and a variance of 16 hours. a) If you randomly pick one-hundred customers, find the probability that the average time spent on hold is within 1 hour of the population mean. Compare the output with the result you obtainedin Question 8 (d) of Part A . (3 marks) b) If you randomly pick 64 customers find the probability that the average time spentin the retail store is at most 7.5 hours. (3 marks) c) If you randomly pick 64 customers find the probability that the average time spentin the retail store is at least 6.5 hours. (4 marks)