Abstract_interfaces_practice_questions
package com.company ; import java.sql. SQLOutput ; abstract class pen { abstract void Refill (); abstract void write (); } class FountainPen extends pen { @Override void Refill () { System . out . println ( "Refiiling" ); } @Override void write (){ System . out . println ( "Write " ); } void ChangeNib (){ System . out . println ( "Changing nib.." ); } } class Monkey { void Jump (){ System . out . println ( "Jump" ); } void Bite (){ System . out . println ( "Biting" ); } } interface BasicAnimal { void eat (); void sleep (); } class Human extends Monkey implements BasicAnimal { @Override void Jump () { super . Jump (); } @Override void Bite () { super . Bite (); } @Override public void eat () { System . out . println ( ...