Exercise 3. Suppose users share a 2 Mbps link. Also suppose that each user transmits only for 20% of the time at 100kbps, and is idle the remaining time. 1. When circuit-switching is used, how many users can be supported? = 2. For the remaining of the problem, assume packet-switching. (i) Find the probability that a given user is transmitting. (ii) Suppose there are N = 40 users. What is the probability that at any given time exactly n users transmit simultaneously? (iii) What is the probability that there are 21 or more users transmitting simultaneously