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What should you do before starting down a hill with a vehicle?

  1. Switch into a neutral gear

  2. Switch into a low gear

  3. Turn off the air brakes

  4. Engage the parking brake

The correct answer is: Switch into a low gear

Before starting down a hill, it is crucial to switch into a low gear. This practice utilizes the engine's power to help control the speed of the vehicle as you descend, which is essential for maintaining safe handling and preventing the brakes from overheating. When you are in a low gear, the engine can provide additional resistance, reducing the reliance on the braking system and allowing for more stable control of the vehicle's speed. Engaging a low gear enhances overall safety, especially when dealing with steep declines, as it helps keep the vehicle from accelerating too quickly. This not only protects the brakes from excessive wear and potential failure but also ensures that the driver maintains better control over the vehicle in challenging conditions. Choosing neutral or turning off the air brakes would compromise braking ability and control, while engaging the parking brake is not appropriate for driving downhill. These alternatives would not provide the necessary support and security that a low gear offers when navigating a gradient.