Let X be the number of packages being mailed by a randomly selected customer at a shipping facility. Suppose the distribution of X is as follows: x 2 1 2 3 4 p(x) 0.4 0.3 0.2 0.1(a) Consider a random sample of size n = 2 (two customers), and let X be the sample mean number of packages shipped. Obtain the probability distribution of X.(b) Refer to part (a) and calculate Pr(X < 2.5).(c) Again consider a random sample of size n = 2, but not focus on the statistic R =the sample range (difference between the largest and smallest values in the sample). Obtain the distribution of R.(d) If a random sample of size n = 4 is selected, what is Pr( X < 1.5)?