In the figure below pi's represent permissions and ei's represent users. Their assignments to roles in the hierarchy are shown by the dotted arrows. a. Find assigned_users(r) and authorized_users(r) for each r in the figure. (10 point) b. Find assigned_permissions(r) and authorized permissions(r) for each r in the figure. (10 points) e5 Pa, Senior Administrator Administrator px, Py Manager e3, ei, e e10 Employee P, P Pp Po Senior Engineer Engineer Pm. Pn er, eg e6 e7