Final answer:
Any load that extends 1.5 meters or more from the rear of a vehicle must be marked with a red flag or sign in daylight or a red light at night.
Step-by-step explanation:
According to traffic regulations, any load that projects from the rear of a vehicle by 1.5 meters (5 feet) or more must be marked with a red flag or sign in daylight or a red light at night. This is to alert other drivers of the protruding load and ensure safety on the road. For example, if a truck is carrying a long object that extends 1.5 meters or more behind the vehicle, it must have proper markings to indicate the potential hazard.