* The length of a football field: A standard football field is 100 meters long.

* Three times the height of a double-decker bus: A double-decker bus is about 30 meters tall.

* The distance a person can run in about 10 seconds at a moderate pace: This depends on the person's speed, of course.

It's a relatively short distance, especially when compared to things like the distance to the moon (384,400 km) or the circumference of the Earth (40,075 km).