all code must be written in C#

- Billing Summary - Here are five output controls that display the results of the calculations described below. All calculations are to be initiated by the user clicking a Total button. When this button is clicked, the program is to calculate five values that are displayed in a column in the Billing Summary area: 1) room charges (the length of the stay in nights times the nightly room rate), 2) additional charges (the sum of the three optional charges described above), 3) subtotal (the sum of the room charges and the additional charges), 4) tax amount (the subtotal times the tax rate, which is currently 7% ), and 5) total charges (the sum of the subtotal plus the tax). Guest infomation Room Infomation Addtional Charges Fest Name: Last Name: Room Number: Mini Bar Charges: Telephone Charges: Dollar Rate: Mic, Charges