1. The problem statement, all variables and given/known data At highway speeds, a particular automobile is capable of an acceleration of about 1.57 m/s2. At this rate, how long does it take to accelerate from 72.0 km/hr to 100.0 km/hr? 2. Relevant equations I was given: vf = vi + at 3. The attempt at a solution Simplifying the velocities I got 28 = 1.57a and a= 17.83 s.