Which of the following are legal assignments? List the statement number.

1. Book b = new Book();

2. Book b = new Dictionary();

3. Book b = new eBook();

4. eBook b = new Book();

5. eBook b = new Dictionary();

6. eBook b = new eBook();

7. Dictionary b = new Book();

8. Dictionary b = new Dictionary();

9. Dictionary b = new eBook();

10. Object b = new Book();

11. Object b = new Dictionary();

12. Object b = new eBook();

13. Book b = new Object();

14. Dictionary b = new Object();

15. eBook b = new Object();