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                <pre class="logger">Output<br></pre>




                //Base/Parent Class
function Person(name, age){ = name || "";
  this.age = age || "";  

//Add a print function to the prototype of Person
Person.prototype.print = function(){
  log("Inside Print function: Name is "" ,Age is "+ this.age);
//Sub-class/Child class.
function Teacher(name, age, subject, salary){
  //Initialize name and age using Person's constructor, name, age);
  // Private sub class variables
  this.subject = subject;
  this.salary = salary;

Teacher.prototype = Object.create(Person.prototype);
Teacher.prototype.constructor = Teacher;

//create instances of Person and Teacher and inspect them.
var person = new Person("Vishal", 34);
//Person has access to print function on it's Prototype

var mathTeacher = new Teacher("Smriti", 45, "Math", 20000);
//Teacher itself doesn't have a print function but on in't prototype chain it has access to Person's prototype.

// create a logger to show things on screen //
function log (content) {
  var output = document.getElementsByClassName("logger")[0],
      content =": ");
  output.innerHTML += content + "<br>";