$5)(25$ points$)$ Consider TCP reliable data transfer of letters A$,$ B$,$ and C$,$ each encoded into eight bytes of data and sent in an individual segment from host X to host Y $.$ The user types a new letter every $1$ seconds. Suppose the first segment carrying A has SeqNumb $\backslash (=65\backslash )$ and $\backslash (\backslash$operatorname$\{$ACK$\}=345\backslash ).$ Suppose the regular one$-$way delay between X and Y $($and vice versa$)$ is $0\mathrm{.}5$ seconds. Suppose all exchanges take the regular delay, but the transmission of letter B from X to Y takes $1\mathrm{.}75$ seconds. Suppose the timeout is sufficiently long to avoid retransmissions.

a$)$ Draw the exchanged segments with SeqNumb, ACK, and carried data.

b$)$ When is each letter delivered to the application layer at Y$?$ give me the exact ans with step by step solution