You are required to create a conceptual data model of the data requirements for a plumbing whole sale company. Following are their business requirements (ERDish): Each salesman has got a sales number, last name, first name, and address (street, city, state, zip, commission, and rate. Every salesman handles one or many customers. Each customer has customer number, customer name, address (street, city, state, zip, balance, credit limit, and salesman number. Each customer can be handled by one and only one salesman. Each order has order number, order date, customer number. Each order includes one or many parts. Each part has part number, description, on hand, class, warehouse, price. Each part can be handled by zero or many orders. Parts quantity per order and quoted price also need to be included when an order has been issued. TO DO a) Identify the main entity types based on the above questions b) Identify the main relationship types and specify the multiplicity for each relationship for each question. State any assumptions you make about the data. Using your analysis answers and results for draw a single ER diagram to represent the data requirements for the company.