Final answer:
Vehicles and other equipment should not be left unattended within 200 feet of a runway centerline.
Step-by-step explanation:
Vehicles and other equipment should not be left unattended within 200 feet of a runway centerline. This is to ensure safety and prevent any potential accidents or damage to the aircraft. Being close to the runway centerline can pose a risk to both the equipment and the aircraft during takeoff or landing.