Exercise 1 Vending Machine. A vending machine sells small, packaged, ready to eat items (chocolate bars, cookies, candies, etc.). Each item has a price and a name. A customer can buy an item, using a smart card (issued by the vending machine company). No other payment method (i.e. cash, credit card) are allowed. The vending machine has a smart card reader that updates the available amount of money on the smart card upon completing the sale process. Each time the customer enters the card, the card is validated for purchase, if it is valid, the process sale will be accomplished, otherwise the card and the process will be rejected. The system supports the following functions: Sell an item (choose from a list of items, pay for an item, dispense an item) Recharge the machine with items Monitor the machine (number of sold items, number of sold items per type, total revenue) Set up the machine (define sold items and price of items) The system can be used by a customer (who buys item),a maintenance employee (who recharges and monitors the machines), an administrator (who sets up the machine). Use starUML to do the following: EHHI CODE song. SHIP CANDY scom Page of 3 3) Draw a Class Diagram that shows the main classes in the above system along with the relationships that may occur between classes.(do this at home)