Use cylindrical coordinates to evaluate the triple integral $\displaystyle \int \!\! \int \!\! \int_{\mathbf{E}} \, \sqrt{x^{2} + y^{2}} \, dV$, where E is the solid bounded by the circular paraboloid $z = 9 - 1 \left( x^{2} + y^{2} \right)$ and the $xy$ -plane.