b. (10 points) Consider a router buffer preceding an outbound link. In this problem, you will use Little's formula, a famous formula from queueing theory. Let N denote the average number of packets in the buffer plus the packet being transmitted. Let a denote the rate of packets arriving at the link. Let d denote the average total delay (i.e, the queueing delay plus the transmission delay) experienced by a packet. Little's formula is N = A d. Suppose that on average, the buffer contains 10 packets, and the average packet queueing delay is 10 milliseconds. The link's transmission rate is 100 packets/sec