The rectangles in the graph below illustrate a left endpoint Riemann sum for f$($x$)=($x$^2)/10$ f$($x$)=($x$^2)/10$ on the interval $[3,7][3,7].$

The value of this left endpoint Riemann sum is $,$ and this Riemann sum is an $?$overestimate of$$equal to$$underestimate of$$there is ambiguity$$ the area of the region enclosed by y$=$f$($x$)$y$=$f$($x$),$ the x$-$axis, and the vertical lines x $=3$ and x $=7.$

The rectangles in the graph below illustrate a right endpoint Riemann sum for f$($x$)=($x$^2)/10$ f$($x$)=($x$^2)/10$ on the interval $[3,7][3,7].$

The value of this right endpoint Riemann sum is $,$ and this Riemann sum is an $?$overestimate of$$equal to$$underestimate of$$there is ambiguity$$ the area of the region enclosed by y$=$f$($x$)$y$=$f$($x$),$ the x$-$axis, and the vertical lines x $=3$ and x $=7.$