On a one-way street, where should you place your warning devices?

On a one-way street, placing your warning devices 10, 100, and 200 feet back is the correct approach because this spacing gives oncoming traffic ample warning to notice any hazards or incidents ahead. The distance of 10 feet is close enough to alert drivers immediately, while the larger distances of 100 and 200 feet provide additional warning to allow sufficient reaction time for vehicles approaching the danger. This method promotes safety on the road by giving drivers enough time to adjust their speed or change lanes if necessary.

The other options suggest varying distances which may not provide adequate warning to drivers, particularly those further away from the incident. By following the prescribed distances, you ensure that the warning devices are effective in alerting drivers in a timely manner, ensuring a safer environment for everyone on the road.