The intake of oxygen by an athlete was measured at the start, during and after a 5000 m race at time intervals of 3 minutes. The results are shown in the table below. (Plot the graph on paper: oxygen intake against time.)

1. aWhat is the amount of oxygen intake at rest? [1]
2. bHow much time did the athlete take to complete the race? [1]
3. cExplain your answer. [1]
4. dFrom 0.02%, 0.04%, 4.0% and 78.0%, choose the percentage of carbon dioxide in exhaled air during the race. [1]
5. eExplain your answer. [1]

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