Answer:
To find the acceleration of a car slowing from 12 m/s to a stop in 15 seconds, we can use the formula a = (vf - vi) / t, where a is the acceleration, vf is the final velocity, vi is the initial velocity, and t is the time. In this case, the initial velocity is 12 m/s, the final velocity is 0 m/s (since the car is coming to a stop), and the time is 15 seconds. Plugging these values into the formula, we get a = (0 - 12) / 15 = -0.8 m/s^2. This means that the car is slowing down at a rate of 0.8 meters per second squared.