An online shop is looking for a WPF app that calculates the total amount of the bill. The app should display an items menu in four ComboBoxes. Each ComboBox should contain a category of products offered by the store (Electronics, Books, Toys and Jewelry). The user can choose from one of these ComboBoxes to add an item to the bill. As each item is selected in the ComboBoxes, the price of that item will be added to the bill. The HST of 18% will be added. The user can click the Clear Bill Button to restore the Subtotal, Tax: and Total: fields to $0.00. Add your student's name and your company's (i.e., Centennial College) logo at the status bar, when user clicks the logo, company's website is opened in Internet explorer.