$($b$)$ Fig. $1$ illustrates the evolution of TCP$\text{'}$s congestion window $($cwnd$).$ The unit of time $($on the x$-$axis$)$ is equal to the Round Trip Time $($RTT$).$ Reconstruct the sequence of events that explains TCP$\text{'}$s cwnd using the following prompts.

Figure $1$: TCP Congestion Window Evolution

$($i$)$ Give the time indices when TCP is in slow start.

$($ii$)$ List the time indices when TCP is in congestion avoidance mode.

$($iii$)$ Give the time indices when TCP is in fast recovery.

$($iv$)$ List the time indices corresponding to packet loss via timeout.

$($v$)$ List the time indices corresponding to packet loss via triple ACK.

$($vi$)$ Give the time indices when the value of ssthresh changes.