Hint for process of elimination: In the vast majority of cases, the SAT problem creators are very careful to make solutions realistic. You may recognize 5 km, or 3.1 miles, to be the standard distance for a 5K, a very common race frequently ran or walked for charity or in local or school competition across the United States. A 5K can be run in 15 minutes for the fastest high school runners, or walked at a comfortable pace in less than one hour. Use this to eliminate the two answers that do not make sense.
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