Answer:
Acceleration value of car = -2

Step-by-step explanation:
We have equation of motion, v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration and t is the time taken.
Here a car is traveling at 12 m/s, so initial velocity = 12 m/s
After 2 seconds the speed drops to 8 m/s, so final velocity = 8 m/s
Time taken = 2 seconds
Substituting
8 = 12 + a * 2
2a = -4
a = -2

Acceleration value of car = -2
