$5.(12$ total points$)$ The position function $\backslash ($ s$($t$)\backslash )$ of an object moving up and down is graphed below. Here the position is in meters above$/$below the starting point, and time is in seconds.

$($a$)(6$ pts$)$ What is the average velocity of the object from $\backslash ($ t$=1\backslash )$ to $\backslash ($ t$=4\backslash )?$ Include units!

$($b$)(6$ pts$)$ Does the average velocity you calculated in $($a$)$ accurately describe the motion of the object between $\backslash ($ t$=1\backslash )$ and $\backslash ($ t$=4\backslash )?$ Why or why not?