What is 'hydroplaning' and how should you recover if your vehicle begins to hydroplane?

1. When the brakes freeze in winter; recover by pumping them hard
2. When a layer of water builds up between the tires and the road, causing a loss of traction; recover by easing off the accelerator, steering straight, and avoiding braking
3. When the radiator leaks water onto the tires; recover by turning off the engine
4. When the vehicle slides on black ice; recover by steering in the opposite direction of the skid