class Media {
  constructor(title, isCheckedOut = false, ratings = []) {
    this._title = title;
    this._isCheckedOut = isCheckedOut;
    this._ratings = ratings;
  }

class Book extends Media {
  constructor(author, title, pages) {
    super(title);
    super(isCheckedOut);
    super(ratings);
    this._author = author;
    this._pages = pages;
  }

const historyOfEverything = new Book ('Bill Bryson', 'A Short History of Nearly Everything', 544);