Read the following scenario and then answer the question.
About halfway through his 1,600-meter race, an athlete loses his footing and trips himself while attempting to pass another runner. He falls to the track and rolls awkwardly but then pops up quickly and continues to run the race. During his fall, however, he scrapes his knee on the track. His knee is bleeding, and although he wipes away the blood with his hand every 20 seconds or so, the cut continues to bleed.
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