The diagram below shows a distance-time graph for a vehicle. It rises steadily from 0 km at 0 h to 300 km at 3 h, then stays at 300 km from 3 h to 4 h.

1. aDefine speed. [1]
2. bDescribe the motion of the vehicle between the times of 3 and 4 hours. [1]
3. cCalculate the speed of the vehicle between 0 and 2 hours. [2]
4. dState how the air resistance on the vehicle compares with its driving force between 0 and 3 hours. [1]
5. eAfter the 4th hour, the vehicle travelled for two hours at a constant speed returning to where it started. Describe the graph for this part. [2]

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