What would be the output of the following code?

class Dog {

constructor(name) {

this.name = name;

}

speak() {

console.log(this.name + ' Barks!');

}

}

class Wolf extends Dog {

speak() {

super.speak();

console.log(this.name + ' Howls at the moon!');

}

}

var l = new Wolf('Fido');

l.speak();