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Inventory Class Design an Inventory class that can hold information and calculate data for items in a retail store's inventory. The class should have the following private member variables: Variable Name Description itemNumber An int that holds the item's item number. quantity An int for holding the quantity of the items on hand. cost A double for holding the wholesale per-unit cost of the item totalcost A double for holding the total inventory cost of the item (cal- culated as quantity times cost). The class should have the following public member functions: Member Function Description Default Constructor Sets all the member variables to 0. Constructor #2 Accepts an item's number, cost, and quantity as arguments. The function should copy these values to the appropriate member variables and then call the setTotalcost function. setItemNumber Accepts an integer argument that is copied to the itemNumber member variable. setQuantity Accepts an integer argument that is copied to the quantity member variable. setcost Accepts a double argument that is copied to the cost member variable. setTotalcost Calculates the total inventory cost for the item (quantity times cost) and stores the result in totalcost. getItemNumber Returns the value in itemNumber. getQuantity Returns the value in quantity. Returns the value in cost. getTotal cost Returns the value in totalcost. getcost