solve 1 & 4

1. We have to calculate the area of a rectangle, a square and a circle. Create an abstract class 'Shape' with 2 dimension fields and an abstract method namely 'area'. Now, write 3 classes 'Rectangle', 'Circle' and 'Triangle' derived from the 'Shape' class. Implement the area() method as necessary in each class. Now create another class 'Geometry' containing the main method and create objects of 'Rectangle', 'Square' and 'Circle' and printing their area. 2. 3. What is the use of 'final keyword? 'final could be used before three things: fields, functions and classes. What happens in each case? Write 2 classes to give examples of function overloading and function overriding. Mention which methods are overloaded and which are overridden. Write class declarations for the class hierarchy given: A 4. B D