[b]Volume of a WASHER: [/b] [br][br]A simple washer can be formed by starting with a cylinder and boring out a hole (another cylinder) so that the bases of 2 cylinders have the same same center and so that both these cylinders have the same height. If this is the case, then [br][br][math]V_{washer}=\pi R^2h-\pi r^2h...[/math][br][br]where[br][br] [i]R[/i] = the radius of the BIGGER CYLINDER[br][i]r[/i] = the radius of the SMALLER CYLINDER[br][i]h[/i] = the height of both cylinders.