1. Consider a packet of size 3000 bytes that begins at a host A and travels over 4 links to a destination host B. The links are connected by 3 packet switches. Suppose the propagation speed is 2.5x108 m/s, the transmission rates on all links are 3 Mbps, processing delay is 4msec, length of first link is 1000km, second link 5000km, third link 4000km and fourth link 2000km. What is the end-to-end delay?