4. Is it possible to declare abstract methods as private?
a. Justify your answer.

5. Is it compulsory for a class, which has been declared as abstract, to have at least one abstract method?

1. Why is encapsulation called Data Hiding?
2. What are the main benefits of using encapsulation in Java?
3. Provide an example of how to achieve encapsulation in Java.
4. Is it possible to declare abstract methods as private?
   1. Justify your answer.
5. Is it compulsory for a class, which has been declared as abstract, to have at least one abstract method?

1. Why is encapsulation called Data Hiding?
2. What are the main benefits of using encapsulation in Java?
3. Provide an example of how to achieve encapsulation in Java.
4. Is it possible to declare abstract methods as private?
   a. Justify your answer.
5. Is it compulsory for a class, which has been declared as abstract, to have at least one abstract method?

class which contains the abstract keyword in its declaration is known as abstract class. But, if a class has at least one abstract method, then the class must be declared abstract. 

(Object Oriented Programming in c++)