Eighty cyclists were each asked the distance (in kilometres) they cycled last week. The cumulative frequency diagram represents the results. Use the graph to estimate [Diagram: cumulative frequency graph showing distance (kilometres) on the x-axis from 0 to 120, and cumulative frequency on the y-axis from 0 to 80]

1. (a)the number of cyclists who cycled between 60 and 80 kilometres,[1]
2. (b)the median distance cycled,[1]
3. (c)the interquartile range for the distance cycled.[2]

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