1. Hosts A and B are each connected to a router R via 100Mbps links as shown.

The propagation delay on each link is 20 µs. R is a store-and-forward device; it begins

relaying a received packet 35 us after it has finished receiving it. Calculate the total time

required to transmit 1250 bytes from A to B

a. As a single packet.

b. As two 5000-bit packets sent one right after the other.