Two disks rotate independently around a common axis. One disk rotates in one direction at $5\mathrm{.}00$ rad$/$s and the other rotates in the opposite direction at $4\mathrm{.}00$ rad$/$s$.$ Each disk has the same rotational inertia of $20\mathrm{.}0$ kg$$m$2.$ What is the magnitude of the net angular momentum of the system? A$)20\mathrm{.}0$ kg$$m$2/$s B$)45\mathrm{.}0$ kg$$m$2/$s C$)70\mathrm{.}0$ kg$$m$2/$s D$)115$ kg$$m$2/$s E$)140$ kg$$m$2/$s