QUESTION 3: (20 marks) a) Explain the FOUR (4) principles of object-oriented programming that you've applied in previous questions. (12 marks) b) Explain the term "Java is Robust". Relate with previous questions. (3 marks) c) Differentiate between checked and unchecked exception (4 marks) d) Explain the basic skeleton of an Applet. (4 marks) e) Explain the use of the following method in Applet creation: public void paint (Graphics g) (2 marks) f) Compare between interface and abstract class. Relate with previous questions