Multiple choice technology programming languages

Given: public abstract interface Frobnicate { public void twiddle(String s) ; } Which is a correct class? (Choose all that apply.)

  1. public abstract class Frob implements Frobnicate { public abstract void twiddle(String s){} }

  2. public abstract class Frob implements Frobnicate { }

  3. public class Frob extends Frobnicate { public void twiddle(Integer i) { } }

  4. public class Frob implements Frobnicate { public void twiddle(Integer i) { } }

  5. public class Frob implements Frobnicate { public void twiddle(String i) { } public void twiddle(Integer s) { } }
Reveal answer Fill a bubble to check yourself
B,E Correct answer
Explanation

An abstract class implementing an interface does not need to implement its methods, making 544165 correct. A concrete class must implement all interface methods; 544168 correctly implements twiddle(String) and overloads it with twiddle(Integer). Other options fail due to syntax errors like abstract methods with bodies or using extends instead of implements.

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