Final answer:
A larger space cushion is recommended on an up-hill to prevent rolling back when you start moving again. It's not specifically necessary to increase the space cushion at stop signs, toll plazas, or intersections, but proper spacing based on conditions is always important.
Step-by-step explanation:
The question asks about when to allow a larger space cushion when stopping a vehicle. When learning about driving safety, it's crucial to understand that a space cushion is the distance you keep between your car and the car in front to allow enough time and space to respond to situations. Specifically, the answer would be to allow a larger space cushion on an up-hill because gravity will cause the vehicle to roll back when starting to move again after a stop. Stopping at a stop sign, at a toll plaza, or at an intersection typically does not require an increased space cushion, but awareness and appropriate distance based on speed and conditions should always be maintained.