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 $13.95 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 ask the user to enter
the letter of the package the customer has purchased (A, B, or C) and the number of hours
that were used. It should then display the total charges.
in all cases, the monthly bill is
fixed amount + rate * hours