Starting at 1.0 m/s, a cheetah runs with a constant acceleration for 4.8 s reaching a speed of 28 m/s. What is the acceleration of this cheetah? a. 6.5 m/s^2 b. 7.2 m/s^2 c. 5.6 m/s^2 d. 5.8 m/s^2 e. 7.7 m/s^2