$($a$)$ Does the following figure indicate which sliding window protocol, stop$-$and$-$wait,

Go$-$Back$-$N$,$ or selective repeat ARQ is being used, or there is no enough information to

tell? Why? $($Explain your answer briefly using one or two sentences.$)[5$ points$]$

$($b$)$ Does the following figure indicate which sliding window protocol, stop$-$and$-$wait,

Go$-$Back$-$N$,$ or selective repeat ARQ is being used, or there is no enough information to

tell? Why? $($Explain your answer briefly using one or two sentences.$)[5$ points$]$

In $41$ co is $4$