Those are JAVA OOP questions, Please help

QUESTION 1

Which of the following is true?

	A.	Abstract and final can be declared on a class
	B.	Abstract and final are contradictory and cannot be declared on a class
	C.	Interfaces can declared as private
	D.	Interface methods can be declared private

QUESTION 2

Suppose:

ArrayList list = new ArrayList<>();

Which of the following operations are correct?

	A.	list.add("Red");
	B.	list.add(new Integer(100));
	C.	list.add(new java.util.Date());
	D.	list.add(new ArrayList());

QUESTION 3

What is the minimum number of methods that must be defined in classB for it to compile with no errors? public interface InterfaceA { void methodA(); } public interface InterfaceB extends InterfaceA { void methodB(); } public class ClassA implements InterfaceA { public void methodA() {} public void methodB() {} } public class ClassB extends ClassA implements InterfaceB { public ClassB() {} ... }

	A.	No particular methods are required
	B.	methodA
	C.	methodB
	D.	methodA and methodB
	E.	methodA , methodB, and toString

QUESTION 4

Which of the following statements causes a syntax error? public interface InterfaceA { void methodA(); } public interface InterfaceB extends InterfaceA { void methodB(); } public class ClassA implements InterfaceA { public void methodA() {} public void methodB() {} } public class ClassB extends ClassA implements InterfaceB { public ClassB() {} ... }

	A.	InterfaceA obj = new ClassA();
	B.	InterfaceB obj = new ClassA();
	C.	InterfaceA obj = new ClassB();
	D.	InterfaceB obj = new ClassB();
	E.	ClassA obj = new ClassB();

QUESTION 5

What is the output of the following code segment? ArrayList names = new ArrayList(); names.add("Sarah"); names.add("Kathy"); for (int i = 1; i < names.size(); i++) { names.add(i, "+"); } System.out.println(names);

	A.	[Sarah, Kathy]
	B.	[Sarah, +, Kathy]
	C.	[Sarah, Kathy, +]
	D.	[Sarah, +, Kathy, +]
	E.	No output because the program goes into an infinite loop

QUESTION 6

Is ArrayList a subclass of ArrayList?

	A.	Yes
	B.	No

QUESTION 7

Suppose ArrayList x contains two strings ["Atlanta", "St Louis"]. Which of the following methods will cause the list to become ["Atlanta", "Chicago", "St Louis"]?"

	A.	x.add("Chicago");
	B.	x.add(0, "Chicago");
	C.	x.add(1, "Chicago");
	D.	x.add(2, "Chicago");

QUESTION 8

Which of the following code is correct?

	A.	ArrayList list = new ArrayList<>(); list.add(5.2);
	B.	ArrayList list = new ArrayList<>(); list.add(5.2);
	C.	ArrayList list = new ArrayList<>(); list.add(5);
	D.	ArrayList list = new ArrayList<>(); list.add("5");

QUESTION 9

What is the size of a variable of type double in Java?

	A.	2 bytes
	B.	4 bytes
	C.	8 bytes
	D.	It depends on the compiler setting
	E.	It depends on the operating system

QUESTION 10

The Gender enum is defined as: public enum Gender { FEMALE, MALE } Which of the following is correct for assigning a gender to a variable g of type Gender?

	A.	Gender g = "FEMALE";
	B.	Gender g = Gender.FEMALE;
	C.	Gender g = new Gender(FEMALE);
	D.	Gender g = Gender->FEMALE;

QUESTION 11

Given: A and B are classes C and D are interfaces Which of the following cannot be true?

	A.	B extends A
	B.	A implements B
	C.	A implements C
	D.	B implements C, D

QUESTION 12

Choose the appropriate data type for this value: 1

	A.	int
	B.	double
	C.	String
	D.	boolean

QUESTION 13

To create a list to store integers, use

	A.	ArrayListlist = new ArrayList();
	B.	ArrayList list = new ArrayList();
	C.	ArrayList list = new ArrayList<>();
	D.	ArrayList list = new ArrayList();

QUESTION 14

The last value in an array called ar can be found at index:

	A.	0
	B.	1
	C.	ar.length
	D.	ar.length - 1

QUESTION 15

Given the declaration : int [ ] ar = {1,2,3,4,5}; What is the value of ar[4]?

	A.	2
	B.	3
	C.	4
	D.	5

QUESTION 16

Which of the following statements is true?

	A.	A static variable cannot have its value set in a constructor
	B.	A static variable must be declared final
	C.	An instance variable can't be declared final
	D.	A static method can't access an instance variable
	E.	Only a static method can access a static variable