c) Write a base class Worker and derived classes HourlyWorker and ContractWorker. Every worker has a name and a salary rate. Write functions compute_pay(int hours) in the base class and derived classes that computes the monthly pay for every worker. For base class, the worker gets paid the hourly wage for 40 hours, no matter what the actual number of hours is. For derived classes, an hourly worker gets paid the hourly wage for the actual number of hours worked. If the hourly worker worked more than 40 hours, the excess is paid at time and a half. The contract worker gets paid by number of project, no matter what the actual number of hours is. Each project completed will get RM500. Write a program using Polymorphism to test the Worker, HourlyWorker and ContractWorker classes by creating instances of them asking the user to fill in data with get_data() and then displaying it using display_salary().