Question 4: (5+5) a. The number of telephone calls at a switchboard during any 10-minute period is known to be Poisson r.v. X with 2 = 2. i. Find the probability that more than three call will arrive during any 10-miute period. ii. Find the probability that no call will arrive during the 10-minnute period. b. Let Y = 1/X bear.v. with pdf fx(x). Find the pdf of Y in terms of fx(x)