a byte oriented stop and wait protocol uses frames of $150$ bytes and acknowledgements of $7$ bytes. the processing delays at the delays at the sender and the receiver are $2\mathrm{.}2$ us each. the physical layer operates at $22$ Mbit$/$s over a cable of length $12\mathrm{.}5$ km$,$ on which signals travel at two$-$thirds the speed of light.