Car Dealership System (20 points) Description of problem domain: the customer goes to the car dealer to purchase a car. First, the customer works with the salesperson who lists available cars from the dealers stock. If the customer finds and selects a car, he may test-drive the car. If he feels satisfied with the car after test-driving, he will negotiate the price with the salesperson. The customer may bring his old vehicle for trade-in. If the customer and the salesperson agree upon the final price (including the trade-in price if the customer has a trade-in car) after negotiation, the customer will work with the finance manager on the payment and possible car loan. If the customer needs a car loan, the finance manager must retrieve the customers credit report from an external credit rating service database. If the customers credit rating (on the credit report) is not good for granting the car loan, the customer and the finance manager will cancel the deal (since the customer cannot pay off the purchase at one time). If the credit rating is good and the car loan is approved, the finance manager processes the car loan and takes any down payment the customer would like to pay. After the payment is completed, the finance manager will exchange the ownership of the car(s) (including the purchased and the traded-in car if any). To exchange ownership, the finance manager and the customer must sign a contract. Now the car sale transaction is completed. Note: 1) When the customer purchases a vehicle from a dealer, they must either pay off the total cost at one time, or get a car loan. If the customer is granted a car loan, they can pay a part of the total cost as down payment and the rest of the cost is paid off by the loan company (e.g., bank) at one time. The customer must pay off the loan to the bank later. In other words, the customer must pay off the total cost to the dealer at one time. Purchasing any products like houses works in the same way the customer must pay off the cost at one time; if they cannot, they need to get a loan which helps pay off the total cost at one time. 2) A contract is the legal document that officially transfers the ownership.

Part 1: Draw use case diagram

Part 2: Draw class diagram (12 points)