Assume that a source sends a packet to the destination and there are $4$ routers on the path. Assume the bandwidth of each link is $100$ Mbps $($Megabits$/$sec$),$ and the size of each packet is $16$ Kb $($Kilobits$).$ Assume the length of each link is $20$ km$,$ and the propagation speed is $2$ x $108$ m$/$s$.$ Assume each router processes a packet for $4$ microseconds $($dproc $=4\backslash$mu s$).$ There is no queueing delay. Calculate the end$-$to$-$end delay to this packet $($from first bit sent until the last bit received$).$