An object moving at 32m/s takes 4s to come to a stop. What is the object’s acceleration?

m/s2

Need help please, have work on this and still cant figure out.

As,

a = (vf-vi)/t
a = 0-32/4
a = -32/4
a = -8 m/s²
Acceleration will be negative i.e, deceleration.