Final answer:
The change in potential energy of the racecar from start to finish is 31376 J.
Step-by-step explanation:
To calculate the change in potential energy of the racecar, we need to determine the change in height from the start to the finish of the track. The vertical drop is 28 m, so the change in height is 28 m. The formula to calculate potential energy is PE = mgh, where m is the mass, g is the acceleration due to gravity (9.8 m/s^2), and h is the change in height. Plugging in the values, we get PE = (113 kg)(9.8 m/s^2)(28 m) = 31376 J.