An Internet service provider has three different subscription packages for its customers:
Package A: For $9.95 per month 10 hours of access are provided. Additional hours are $2.00 per hour.
Package B: For $14.95 per month 20 hours of access are provided. Additional hours are $1.00 per hour.
Package C: For $19.95 per month unlimited access is provided.
Write a program that calculates a customer's monthly bill. It should input customer name, which package the customer has purchased, and how many hours were used. It should then create a bill that includes the input information and the total amount due. The bill should be written to a file.
Input Validation: Be sure the user only selects package A, B, or C. Also, the number of hours used in a month cannot exceed 744.