Suppose that there are 20 different types of coupons and you wish to collect all of them. You collect one coupon every day, and it is equally likely for you to collect any of the 20 types (a) What is the expected number of distinct coupon types that you obtain in 60 days? (b) Let X be the number of coupons that you collect until you have all 20 types. What is the expected value of X? What is the variance of X?Suppose that there are 20 different types of coupons and you wish to collect all of them. You collect one coupon every day, and it is equally likely for you to collect any of the 20 types (a) What is the expected number of distinct coupon types that you obtain in 60 days? (b) Let X be the number of coupons that you collect until you have all 20 types. What is the expected value of X? What is the variance of X?