Answer Happy

please help i am stuck
2. Suppose XX is an abstract class, YY is a concrete subclass of XX, and both XX and Y have a default constructor. Which of the following is correct? a) XX x = new XX(); b) xx x = new YY(); c) YY y = new XX(); d) Both a) and b) e) All of the above f) None of the above 3. Which of the following is a valid declaration? a) public final abstract class Test{ } b) public final interface Test{ } c) public final class Test{} d) Both a) and b) e) All of the above f) None of the above