Calculate a Riemann sum $3,3 on the square R = [0, 3] x [0, 3] for the function g(z, y) = f(z, y) + 3. The contour plot of f(I, y) is shown in Figure 4. Choose sample points and use the plot to find the values of f (z, y) at these points. Use the values of f (x, y) to evaluate g(x, y) accordingly 23 32 i 22 5 3 X FIGURE 4 Contour plot of f (I, y). S3,3