A car travels a certain distance along a straight road and on the way must stop at traffic lights and obey the local speed limits. The Figure shows the distance the car travels as function of time. Choose all the correct answers (i.e., B, AC, BCD . . .) which apply to the speed of the car. A) The speed is zero at 0.5 min and 4.1 min. B) The speed at 2.1 min is greater than at 6.4 min. C) The speed doesn't change from 3 to 4.1 min. D) The speed at 2.5 min is greater than at 2.2 min. E) At 2.1 min, the speed is as high as it gets.


Refer to the Figure and choose ALL the correct answers which apply to the acceleration of the car. A) The acceleration is zero at 0.5 min and 4.1 min. B) The acceleration is non-zero at 6.4 min. C) The acceleration is never negative. D) The acceleration is non-zero at 2.1 min. E) The acceleration is not zero at 3.3 min. HINT: Acceleration is the rate of change of speed, i.e., acceleration = (change in speed)/(time elapsed). If the speed is changing there must be an acceleration.

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