<u><em>21% of the atmosphere is Oxygen. </em></u>
No conclusive evidence exists on “average” 1-mile run times, because there is no scientifically agreed-upon average runner. Opinion varies widely, but most anecdotal evidence places the average between seven and 10 minutes per mile for a non-competitive, in-shape runner.
Answer:
Friction force is independent of the direction of the contacting surfaces
Explanation:
It can go any way depending on how much force is being out on it.
