What should be done if you need to park a combination vehicle on a hill?

When parking a combination vehicle on a hill, it is crucial to prevent the vehicle from rolling, which could lead to dangerous situations. The correct approach is to turn the wheels towards the curb and engage the parking brake. This action ensures that if the vehicle were to move, the wheels would come into contact with the curb, helping to stop any potential movement downhill.

Turning the wheels towards the curb provides an additional layer of safety beyond just engaging the parking brake, as it physically positions the vehicle in a way that utilizes the curb as a barrier. Engaging the parking brake alone, while important, does not account for the force of gravity that could overcome the brake if the vehicle were to roll.

Some other practices, like leaving the vehicle in neutral, would be inappropriate and unsafe, as it could lead to the vehicle rolling freely. Similarly, relying solely on wooden blocks without additional safety measures does not provide adequate security against movement. Therefore, combining the turning of the wheels towards the curb with the engagement of the parking brake is the most effective strategy for parking a combination vehicle on a hill safely.