The diagram shows the speed-time graph for 70 seconds of a car's journey. After 20 seconds the car reaches a speed of v m/s. During the 70 seconds the car travels 1375 m. [Diagram: speed-time graph showing a trapezium shape, with a rise from t=0 to t=20 reaching speed v, then constant speed v from t=20 to t=60, then falling from t=60 to t=70 reaching speed 0]

1. (a)Calculate v.[2]
2. (b)Calculate the acceleration of the car during the first 20 seconds.[1]

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