Develop an Entity-Relationship model for the purchasing requirements described below.
1. The purchasing department of a company issues purchase orders (PO) to its suppliers.
2. Each PO is for one supplier.
3. Each PO has one or more line items (PO LINE ITEM).
4. Each line item belongs to one PO.
5. Each line item is for one product from a supplier.
6. A supplier may supply one or more products.
7. A product from a supplier could be in multiple purchase orders.
8. The status of a PO is tracked at the line item level. Example of statuses are “line item shipped”, “line item received”, “line item rejected”, “line item paid”, etc.
Use the formats introduced in Chan (2013) for all your models.