$c=5$

$16.$ Below is a graph of $f(x).$ Let $A$ be the area under the curve of $y=f(x)$ from $x=-1$ to $x=1.$ We approximate the area $A$ by four rectangles. Let $L_4$ be the approximation using left endpoints and $R_4$ be the approximation using right endpoints. Rank $A,L_4,R_4$ from smallest to largest.

$($A$.)A{L}_4$

$(E.)A{R}_4$

$(D.)L_4$

$(E.)A{L}_4$

$(C.)R_4$

$(D.)L_4$

$(E.)A{R}_4$

$(B.)L_4$

$(C.)R_4$

$(D.)L_4$

$(E.)A$