Design and create a program to calculate the total wages for an employee. An employee is paid $10 per hour for the first 40 hours. The employee is paid $15 per hour for every hour greater than 40 hours and up to 50 hours. The employee is paid $20 per hour for any hours above 50 hours. The program will ask the user to enter the total number of hours (double), and the program will calculate the total wages (show 2 digits to the right of the decimal point.) If the user enters an invalid number of hours (hours <= 0), then display an error message and terminate the program (use "return 0;" to terminate pgm).