Because the main shape is a cube and a cube has all sides equal in length, the volume (l*w*h) is 4*4*4=64. No pi in that volume. Just 64 ft^3. The volume for a cylinder is [tex]V= \pi r^2h[/tex]. The radius is 2 feet and the height is the same as the height of the cube from which it was removed. So volume for the cylinder is [tex]V= \pi (2)^24[/tex] which is [tex]16 \pi [/tex]. Since we are removing the volume of the cylinder from the volume of the cube, the volume remaining, in terms of pi is [tex]64-16 \pi ft^3[/tex]