Modify the Inventory Program by creating a subclass of the selected product's class that uses one additional unique feature of the product that has been selected for you. You must use the subclass name and additional unique feature
based on the information provided below. In the subclass, create a method to calculate the value of the inventory of a product with the same name as the method previously created for the product class. The subclass method should also add a 5% restocking fee
to the value of the inventory of that product. Modify the output to display this additional feature you have chosen and the restocking fee. Selected Product's Subclass: The subclass of your product will be Smart Phones. This means that your subclass must be
called "SmartPhone", and it will extend your "Mobile Phone" class. The additional feature will be "Mobile OS". This data member should be of type "String".