Consider the solid S described below. The base of S is a circular disk with radius 3r. Parallel cross-sections perpendicular to the base are squares. Find the volume V of this solid. I tried this.... A(x) = pi*r^2 = pi*(3r)^2 = pi*9r^2 V(x) = integral from 0 to 3r(pi*9r^2 dx) = pi*27r^3 Am I approaching this problem the wrong way? Thanks for the help!