What is the acceleration of the object? What is the acceleration of the object?
in m/s2

Answer:
-2.5 m/s^2
Explanation:
v=u + at
or, a=(v-u)/t = (10-40)/12=-30/12=-2.5 m/s^2
Here, '-' indicates deceleration is occurring as the velocity is dropping with time.
Hope, this helps you.