Thank you for your time and efforts in advance, I will rate by the moderator

C++ code: Please follow this output. First step: if the user select C, will display the monthly bill and prompt the user for selection again. If the user selected A, it will display as in the figures below and prompt the user to select again. If the user selected B, it will display the results on the figure below and ends.

(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 program that calculates a customer's 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. See the following example for the correct input and output formatting. Input validation: be sure the user only enters A or a for package A, B or b for packageBand C or c for package. 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). CAWindows\system32\cmd.exe Windows system32.cmd.exe Select package (A, B, or C): C Select package (A, B, or C: Total monthly bill is: $59.99 Select package (A, B, or C): Windows\system32\cmd.ee Select package (A, B, or C): C Total monthly bill is: $59.99 Select package (A, B, or C): A Enter number of minutes used: C:\Windows\system32\cmd.exe Select package (A, B, or C: C Total monthly bill is: $59.99 Select package (A, B, or C): A Enter number of minutes used: 2000 Number of extra minutes used: 1100 Your base, monthly bill is $29.99 Your monthly extra charges : $495. Total monthly bill is $524.99 Select package (A, B, or C): B Enter number of minutes used: 3450 Number of extra minutes used: 1650 Your base, monthly bill is $39.99 Your monthly extra charges Total monthly bill is ': $534.99 Press any key to continue