class Test {
  public static void main(String[] args) {
    Honkable[] arr = new Honkable[2];
    arr[0] = new Car();
    arr[1] = new Goose();
    // observe that I can treat a Car and a Goose in
    // exactly the same way because they are both
    // Honkable
    System.out.println(arr[0].honk(5));
    System.out.println(arr[1].honk(5));
  }
}