C. Write an equation for each statement. Then, solve the equation.
5. E varies jointly as M and the square of V.
6. The volume, V, of a gas varies directly as the temperature, T, and inversely as the pressure P.
7. The mass, M, of a cement block varies jointly as the length, L, width, W, and thickness, T, of the block.
8. P varies directly as the square of V and inversely as R.​