JAVA Interfaces and Abstract Classes
Given the following piece of code:public interface Guard{ void doYourJob();}abstract public class Dog implements Guard{ }which of the following statements is correct?

This code will not compile, because method doYourJob() in interface Guard must be defined abstract.
This code will not compile, because class Dog must implement method doYourJob() from interface Guard.
This code will compile without any errors.
This code will not compile, because in the declaration of class Dog we must use the keyword extends instead of implements.

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JAVA Interfaces and Abstract Classes
What will be the output when the following program is compiled and executed?abstract class TestAbstract{ String my_name; String myName(){ my_name = "Examveda"; return my_name; } abstract void display();}public class Test extends TestAbstract{ void display(){ String n = myName(); System.out.print("My name is "+ n); } public static void main(String args[]){ Test t = new Test(); t.display(); }}

Compilation error as class can not be declared as abstract.
None of these
Program will compile and execute successfully and prints
Program compiles but leads to runtime exception.
Compilation error occurs as the abstract class TestAbstract contains a non-abstract method.

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JAVA Interfaces and Abstract Classes
Which of the following statements regarding abstract classes are true?

A subclass can override a concrete method in a superclass to declare it abstract.
A subclass of a non-abstract superclass can be abstract.
All of these
An abstract class can be extended.
An abstract class can be used as a data type.

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JAVA Interfaces and Abstract Classes
What will happen after compiling this program code?abstract class MyClass{ //line 1 private int a, b; public void call(int a, int b){ this.a = a; this.b = b; System.out.print(a+b); }}public class Test{ public static void main(String args[]){ MyClass m = new MyClass(); //line 2 m.call(12,25); }}

Compilation error due to line 1
Successful run and print 37
Compilation error due to line 2
None of these
Runtime error

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JAVA Interfaces and Abstract Classes
Given the following piece of code:public class School{ public abstract double numberOfStudent();}which of the following statements is true?

The method numberOfStudent() in class School must have a body.
You must add a return statement in method numberOfStudent().
The keywords public and abstract cannot be used together.
Class School must be defined abstract.

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JAVA Interfaces and Abstract Classes
What will be the output?1. public interface InfA{2. protected String getName();3. }public class Test implements InfA{ public String getName(){ return "test-name"; } public static void main (String[] args){ Test t = new Test(); System.out.println(t.getName()); }}

None of these
test-name
Compilation fails due to an error on lines 2
Compilation fails due to an error on lines 1
Compilation succeed but Runtime Exception

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