7) (10 points) Suppose there are exactly two routers between a sending host and a receiving host. As shown below, the transmission rate of each link is R. Suppose N packets simultaneously arrive to router 1 and no other packets are currently being transmitted or queued in the network. Each packet is of length L a) What is the average queuing delay for the N packets at router 1? Suppose the q aitat...+g)/ N. router 1 router 2 b) What is the average queuing delay for the N packets at router 2