Acceleration can be measured or calculated by plugging the numbers gathered into the acceleration formula. It is final velocity minus initial velocity and then divides that number by the time. Velocity is measured in meters per second and time is measured in seconds. Acceleration is measured in meters per second squared. To find the answer to the problem, you first need to subtract final velocity which is 2 meters per second from the initial velocity which is 12 meters per second.
This is negative ten. Then divide that by four seconds. The answer, when calculated, will be 2.5 meters per second squared west. Since the car is traveling east, then the negative makes the answer change to the west because it is the opposite.