Analyzable Interface Modify the CourseGrades class you created in Programming Challenge 5 so it implements the following interface: public interface Analyzable {double getAverage(); GradedActivity getHighest(); GradedActivity getLowest();} The getAverage method should return the average of the numeric scores in the grades array. The getHighest method should return a reference to the element of the grades array that has the highest numeric score. The getLowest method should return a reference to the element of the grades array that has the lowest numeric score. Demonstrate the new methods in a complete program