Use cylindrical coordinates. Evaluate xdV, where E is enclosed by the planes z = 0 and z = x + y + 6 and by the cylinders x2 + y2 = 4 and x2 + y2-9. Use cylindrical coordinates. Evaluate x dV E , where E is enclosed by the planes z = 0 and z = x + y + 6 and by the cylinders x