Three students A, B, and C walk together from a school to a bridge. The students rest together on the bridge for 
and then return separately to school. The distance-time graphs of the motion of the three students are shown below:
Determine the distance from the school to the bridge.
Calculate the average speed of the students when they are walking to the bridge. Give your answer in 
.
The students return to school at different speeds. One student walks slowly, one student
walks quickly and the other student runs. State which student runs. Explain how this is shown by the graph.
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