CIS Software Sales:

I need help with this CIS Problem about software sales I am very lost. Please use C# & Visual Studio. Also please use modules, my teacher said its extremely important.

7. Software Sales A software company sells a package that retails for $99. Quantity discounts are given according to the following table: Quantity 10-19 20-49 50-99 100 or more Discount 20% 30% 40% 50% Design a program that asks the user to enter the number of packages purchased. The program should then display the amount of the discount (if any) and the total amount of the purchase after the discount