Suppose users share a 2 mbps link. also suppose each user transmits continuously at 1 mbps when transmitting, but each user transmits only 20 percent of the time. (consider statistical multiplexing discussed in lecture.) (a) (3 points) when circuit switching is used, how many users can be supported? (b) (3 points) for the reminder of this problem, suppose packet switching is used. why will there be essentially no queuing delay before the link if two or fewer users transmit at the same time? why will there be a queuing delay if three users transmit at the same time? (c) (3 points) find the probability that a given user is transmitting. (d) (6 points) suppose now there are three users. find the probability that at any given time, all three users are transmitting simultaneously.