$2\mathrm{.}0.$ Suppose the path from A to B has a single switch S in between: A$$S$$B$.$ Each link has a propagation delay of $60$sec and a bandwidth of $2$ bytes$/$sec$.$

$($a$).$ How long would it take to send a single $600-$byte packet from A to B$?$

$($b$).$ How long would it take to send two back$-$to$-$back $300-$byte packets from A to B$?$

$($c$).$ How long would it take to send three back$-$to$-$back $200-$byte packets from A to B$?$

need help on question $3\mathrm{.}0$

$3\mathrm{.}0.$ Repeat parts $($a$)$ and $($b$)$ of the previo

us exercise, except change the per$-$link propagation delay from $60$sec to $600$sec$.$