“Edwards Air Force base has one runway 15,000 feet long, another is 12,000 feet long, and a third is 8,000 feet long.”
You’re confusing them with numbers.
One mile is 5,280’. So your examples show one almost three miles, one over two miles, and a third over a mile long.
Most people do not know how many feet are in a mile.
God help us if Americans do not jnow how many feet there are in a mile.
I work for a manufacturing firm. We have a drafting department where I would bet only about 4 out of 16 know how many feet are in a mile, or how many yards are in the same mile.
Just ask someone you know for the answer, you may be shocked at the lack on knowledge.