Consider the following environment of a university. There are academic departments. Each department has a chairperson. Each department offers a set of courses. Some courses are currently offered. Some courses need prerequisite. An offering of a course is called a class or class section. A class is taught by a professor. It meets at a particular location. A course may have several sections with different meeting times. Some classes are scheduled in computer lab rooms. University staffs are in charge of lab management. Not all departments offer the summer courses. Each faculty member is assigned to a single department and has a rank. Each student has an academic status $($undergraduate$,$ graduate, non$-$degree$).$ Each student is currently enrolled in a number of classes. Some students are in double majors. Some students are performing better because they are hard working. Students' financial aids depend on their academic performance. Graduate students can have individual faculty as their advisor in writing research thesis. Many students join some club$($s$)$ in the university. Each club has a title, description and contact $($name of a person and the email$).$

$2$b$1.$ Create an ER model for the information in this environment. Hint: this model should include a weak entity, a supertype$-$subtype entity and a recursive relationship.

$2$b$2.$ What information given in above narrative that you cannot model using ER diagram?