Add to your solution in Exercise 2 by including two more sizes, XSmall and XXLarge. Add statements that process the order by calculating the total cost. Each shirt is $16 except the XSmall and...

Add to your solution in Exercise 2 by including two more sizes, XSmall and XXLarge. Add statements that process the order by calculating the total cost. Each shirt is $16 except the XSmall and XXLarge; their specialty prices are $20.00 each. Include an “Add to Cart” option from the “Process” menu that enables the user to add multiple selections to the order. Allow users to purchase different sizes on the same order. The “Display Order” option should be modified so that it displays the total cost for each selection and the final cost for the order. Include an additional “Help” menu option that displays instructions to the user indicating that they can make multiple size selections on a single order.