$,$ Show$/$Hide $1$ position versus time for a certain particle moving along the $x-$axis is shown in the figure below. Find the average velocity in the following time intervals.

$($i$)$

$($a$)0$ to $2\mathrm{.}00s$

b$)2sec-4sec,$

c$)$Also find distance, displacement, average speed and average velocity for the whole journey$(0-8$sec$)$