Which of the following is true about the average acceleration of Car 1 and the acceleration of Car 2 during the time interval shown? A. Car l's average acceleration is nonzero and twice that of Car 2. B. Car 2's average acceleration is nonzero and twice that of Car 1. C. Car 1's average acceleration is nonzero and equal to that of Car 2. D. Both cars have an average acceleration of zero.