4. Given the following business scenario, create a Crow's Foot ERD using a specialization hierarchy if appropriate A professor may advise many students" and "a professor may chair one department." Modify the design shown in Figure 4.36 to include these business rules: An employee could be staff or a professor or an administrator. * A professor may also be an administrator. Staff employees have a work level classification, such a Level I and Level I .Only professors can chair a department. A department is chaired by only one professor. eOnly professors can serve as the dean of a college. Each of the university's colleges is served by one dean. .A professor can teach many classes. . Administrators have a position title. Given that information, create the complete ERD containing all primary keys, foreign keys, and mairn attributes