Ashton Auto Place is a new auto dealer in the town where you can buy new as well as used cars of all makes. Ashton Auto Place uses computerized Transaction Processing System (TPS) to process all sales transactions. Whenever Salesperson sells a Car, the Salesperson enters sales data (which includes customer information, details of the car, and sales information) using the TPS. The system prints sales invoice for the customer, daily sales statement for each Salesperson. The Account Manager periodically logs into the system to view sales activities as well as prints some reports for management. Using the above described business scenario do following:

(a). Draw the context-level Data Flow Diagram (DFD) for the TPS

(b). Identify the entities for which system need to save data. Then draw entity relationship diagram (ERD).