A contour map is shown for a function $\displaystyle {f}$ on the square $\displaystyle {R}={\left[{0},{4}\right]}\times{\left[{0},{4}\right]}$

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Use the Midpoint Rule with $\displaystyle {m}={n}={4}$ to estimate the value for $\displaystyle \int\int_{{R}}{f{{\left({x},{y}\right)}}}{d}{A}$