_________ can be used to slow the vehicle while you are driving down a hill.

The parking brake and the emergency brake are two different names for the same thing. They are used to stop the vehicle in the event of an emergency, such as a brake failure. When driving down a hill, it is important to use the parking brake or the emergency brake to help slow the vehicle and prevent it from accelerating. To do this, simply apply the parking brake or the emergency brake gently while keeping your foot on the brake pedal.