Mobile Service Bill)

A mobile phone service provider has three different

subscription packages for its customers:

Package A: For $29.99 per month 900 minutes are provided. Additional

minutes are $0.45 per minute.

Package B: For $39.99 per month 1800 minutes are provided. Additional

minutes are $0.30 per minute.

Package C: For $59.99 per month unlimited minutes provided.

Write a C++ program that calculates a customers total monthly bills. It should ask which

package the customer has purchased and then ask how many minutes were used. It

then displays a bill showing the base bill charges (29.99, 39.99 or 59.99), the extra

charges (if any) and the total monthly bill.

Input validation:

be sure the user only enters A or a for packageA, B or b for

packageB and C or c for packageC. If the user inputs some other value display an error

message saying Invalid input. When you ask the user to input the number of minutes

and the user enters a negative value you should display the same error message

(Invalid input). In both cases, after you display the error message your program

should stop (exit)