And rectangle each class shall have the following functions double getarea
src/lab11/Circle.java -- A subclass (child) of Shape2D.
src/lab11/RightTriangle.java -- A subclass (child) of Shape2D.
src/lab11/Circle.java -- A subclass (child) of Shape2D.
src/lab11/RightTriangle.java -- A subclass (child) of Shape2D.