pls help and explain pls

1. Define the following class hierarchy for shapes: (a) Define an abstract class Shape. Shapes have a color (which can be a string for now) and a boolean indicating whether or not they are flled. These should be (b) Define an abstract class Shape2D that extends Shape. This class should define (c) Define a class Rectangle that extends Shape2D. A rectangle has a height and properly encapsulated the abstract method getArea() that returns the area of a a Shape2D. a width. Implement the getArea method appropriately. Use the @Override annotation (d) Define a class Square that extends Rectangle. The class should have an ap- propriate constructor and also override setter methods as approrpiate to preserve squareness." (e) Define a class Ellipse that extends Shape2D. An ellipse has a semi-major axis a and a semi-minor axis b (look it up if needed). The area of an ellipse is A ab (f) Define a class Circle that extends E11ipse. You need appropriate contruc- tor(s) and setter(s) for the class. Illustrate all of these with a main method in a separate test class