Final answer:
Regarding an extending load from a vehicle, a red flag must be used for visibility, which increases safety on the road. The flag should be a minimum of 18 inches square and clearly visible, with a red light also required at night.
Step-by-step explanation:
When transporting a load that extends more than four feet beyond the rear of a vehicle, it is crucial to adhere to specific safety regulations to ensure the visibility of the overhanging load to other road users. The appropriate color for the flag that must be attached to the end of the load is red. This requirement is outlined in traffic laws to enhance safety and minimize the risk of accidents on the road. During daylight hours, the red flag must be a minimum of 18 inches square and clearly visible to drivers approaching from behind. At nighttime, in addition to the red flag, the load should be marked with a red light that is visible from a distance. It is essential for drivers to follow these regulations strictly as they contribute significantly to road safety for both the vehicle carrying the extended load and other road users.