An example diagram can be found below: Read the following cases and create ER diagrams using ERDplus. Draw each diagram on the same workspace and save it as HW$1.1)$ At a university, every professor teaches at least one course and can teach as many courses as they want per semester. Each course is taught by only one professor. A course is normally delivered on$-$ground in an assigned classroom, and a classroom can be used by many courses, or sometimes left unused in a semester. A building has many classrooms and a classroom must be in a building. $2)$ In a grocery store, customers shop, then pay and get a receipt. A purchase receipt can contain many products. A product can show up many times on a receipt. Each receipt is produced for one customer at a time. Customers can have many receipts $($produced at different shopping times$).3)$ In a car maintenance shop, there are jobs $($e$.$g$.$ oil change, car wash, etc.$).$ A customer can order one or more of these jobs. A job can be ordered by many customers. Jobs use supplies $($e$.$g$.$ oil, cleaner, etc.$).$ A supply item can be used in many jobs and a job can use many supplies. $4)$ A company sells products, each of which has a productid, name and price. These products are sold to customers who have customerID, name, and ZIP code. Products are purchased through purchase transactions with a transactionID and transaction date. Multiple products can be purchased in a single purchase transaction while a customer can make multiple purchase transactions. When done, click on menu and save your diagram as a picture in your own computer. Then submit it back to Canvas.