abstract class Vehicle { public int speed() { return 0; }class Car extends Vehicle { public int speed() { return 60; }class RaceCar extends Car { public int speed() { return 150; }...RaceCar racer = new RaceCar();Car car = new RaceCar();Vehicle vehicle = new RaceCar();System.out.println(racer.speed() + ", " + car.speed() + ", " + vehicle.speed());