Find the volumes of the solids generated by revolving the triangle with vertices (2,2), (2,8), and (4,8) about a) the X-axis, b) the y-axis, c) the line x = 7, and d) the line y = 2.
The volume of the solid generated by revolving the triangle with vertices (2,2), (2,8), and (4,8) about the x-axis is cubic units.
(Type an exact answer, using it as needed, or round to the nearest tenth.)