3. You have been tasked to estimate the volume of a gravel mound whose base R is a square with side 8 meters. The height of the mound in meters, sampled at Z-meter intervals, is given by the table below. Estimate the volume of the mound as the average of four Riemann sums, where each Riemann sum uses a subdivision of the region into 16 squares, and where the sample points are the lower-left, lower-right, upper-right, and upper-left corners, respectively. (This is a two-dimensional version of the trapezoid rule.) x\\y02468 0.34 0.65 0.81 0.47 0.23 0.45 1.21 1.55 1.33 0.35 0.77 1.49 2.33 1.45 0.61 0.51 1.17 1.34 1.09 0.43 0.31 0.38 0.55 0.44 0.29 OG-FNO