Consider a packet switched network: a$.$ Develop an equation for the end$-$to$-$end delay along a communications path of n routers. The only constant that you may assume is the speed of light in the given transmission medium is $2*108$ m$/$sec$.$ Identify each if the variables in your equation. b$.$ If the distances between nodes were constant $($L$)$ and each node $($end systems and routers are nodes$)$ can transmit R bits per second, what would the equation in $($b$)$ look like?