You Are Given Function $f$ Defined on an Interval $[ a , b ]$

Essay

You are given function $f$ defined on an interval $[ a , b ]$ , the number $n$ of subintervals of equal length $\Delta x = \frac { ( b - a ) } { n }$ , and the evaluation points $c _ { k }$ in $\left[ x _ { k - 1 } , x _ { k } \right]$ .
(a) Sketch the graph of $f$ and the rectangles associated with the Riemann sum for $f$ on $[ a , b ]$ , and
(b) find the Riemann sum.
$f ( x ) = 2 x - 3 , \quad [ 0,2 ] , \quad n = 4 , \quad c _ { k }$ is the right endpoint