Extend your class Rational to include operator methods for addition, subtraction, multiplication and division, and to have friend operator << and operator >> functions for reading and printing the Rational objects. Allow cascaded input and output with the << and >> operators. Do not remove the old Add(), etc., methods. The operator >> and << friend functions need to allow you to pass in either cin or cout (as appropriate) or file handles. Write a new calculator to loop reading Rational objects and operators, exactly as before except using the << and >> operator functions to print and read the Rational objects, and using the operator methods to perform the indicated operations.