Conclusion A running track with a hard surface makes for greater running speed than a soft one, at least under dry conditions, because even though step length is shorter on a hard surface, the time the runner's foot remains in contact with the running surface is less with a hard surface.
The author concludes that a hard track allows for faster running than a soft track, provided the conditions are dry. Why? Because on a hard track, runners spend less time with their feet touching the ground, even though their steps are shorter.
The author assumes that runners save more time by keeping their feet off the ground than they lose by taking shorter steps on a hard track. In addition, he assumes there’s no other feature of hard tracks that allows people to run faster on them.
Which one of the following, ██ █████ ██ ████████ ████ ███ ███████████ █████ █████ ██ ████ █ ███████ ████
Dry running conditions ███ ██ ██████████ ███ ██████ █████ █████ █████
In general, taller ███████ ████ ███████ ███████ ████ ██████ ████ ███████ ███████ ███
Hard tracks enhance █ ████████ █████ ██ ██████ ██ ██████ ███ ███ ██████ ██ ████████ █ ███████ ████ █████████ ████ ███████████
The tracks at █████ ███ ███████ ███████ ███████ █████ ████ ████ ████████ ███ ███████ ████ █████ ███ ██████ █████ ███ ███ ██ ██████████ █████
To remain in ███ ██████████ █ ████ █████ ███████ ████████ █████████ ███████████ ██████████ ████ ████ █ ████ ████