$7(6$ pts$).$ The graph shows the rate of change of enrollment $($i$.$e$.,$ number of students enrolled per year$)$ at a community college in years since $2000.$ Estimate the total change in enrollment between $2002$ and $2008.$ Use a left$-$hand estimate with $n=3$ terms.

$7.q,$

vate $($students per years$)$

$($amas