Question: Draw a sequence diagram for this application.

Consider a Sale Process Scenario for a cashier processing sale activities in a supermarket. The cashier is required to process any purchasing (sale) activity by the customer. The customer will firstly put their goods on the cash counter. The cashier will then enter the item ID (could be the barcode) and its quantity, so that the system can give the description of the item and total price. The process is repeated until all items are scanned and recorded as sale. The process will end afterwards, and will require the customer to pay the amount indicated.

The Use Case has been thoroughly analysed and identified as below:

1. Cashier initiates a new sales record.

2. Cashier checks in product.

3. System retrieves product description and price.

4. System add product to sales record.

5. System repeats check in and adding until all products is checked-in.

6. System calculates total price of sale and indicates to cashier.

7. Cashier process payment by customer.