ConsiderapacketoflengthLthatbeginsatendsystemAandtravelsoverthreelinks to a destination end system. These three links are connected by two packet switches. Let di$,$ si$,$ and Ri denote the length, propagation speed, and the transmission rate of link i$,$ for i$=1,2,3.$ The packet switch delays each packet by dproc. Assuming no queuing delays, in terms of di$,$ si$,$ Ri$,($i$=1,2,3),$ and L$,$ what is the total end$-$to$-$end delay for the packet? Suppose now the packet is $1,500$ bytes, the propagation speed on all three links is $2\mathrm{.}5$ X $108$ m$/$s$,$ the transmission rates of all three links are $2$ Mbps$,$ the packet switching delay is $3$ msec, the length of first link is $5,000$ km$,$ the length of the second link is $4,000$ km$,$ and the length of last link is $1,000$ km$.$ For these values what is end to end delay?