You will design an Entity$-$Relationship $($ER$)$ diagram for a university's data management

system which models information about academic staff and the classes they facilitate. Here are

the specifications:

Professors: Identified uniquely by a Professor ID $($PID$).$

Courses: Identified uniquely by a Course ID $($CID$).$

You will focus on the 'Offers' relationship set between professors and courses. For each given

scenario, draw a distinct ER diagram that models the specific situation. Adhere to the ER

notation taught in the course as alternative notations will not be accepted.

Scenarios to model:

Professors may teach the same course across different terms, with each instance

$($offering$)$ requiring recording in the database.

Professors may teach the same course across different terms, but it is only necessary to

record the most recent such offering. $($Note: This assumption holds for all the following

scenarios.$)$

Each professor is responsible for teaching exactly one course.

Each professor is responsible for teaching exactly one course, and each course must be

taught by some professors.

Every professor must be teaching at least one course.

Certain courses can be taught by a group of professors together. In such cases, it may not

be feasible for a single professor to teach the same course independently. Model this

scenario which may need the addition of new entities and$/$or relationships.