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                <p>Open the JS console to see the results.</p>




                // Vehicle - parent
function Vehicle(name) { = name;
// parent method
Vehicle.prototype.start = function() {
  return "Engine of " + + " starting...";

// Car - child
function Car(name) {, name); // call super constructor.
// child extends parent
Car.prototype = Object.create(Vehicle.prototype);
// child method
Car.prototype.start = function() {
  console.log("Gidday! " +;

// Van - child
function Van(name) {, name); // call super constructor.
// child extends parent
Van.prototype = Object.create(Vehicle.prototype);

// instances of children
var c1 = new Car("Infiniti G37");
var c2 = new Car("Ford Mustang");
var v1 = new Van("Dodge Caravan");

// accessing the subclass method which internally access superclass method
//using parent start()
// add our own start() method 
Van.prototype.start = function() {
  console.log("Hello! " +;