solution:
Given information: u =12m/s
v=6m/s
t=3s
we have formula: v= u+ at
a=v-u/t
a=6-12/3
a=-2m/s2
by this answer, we can say the body is in decelarated motion.
2.A bus starting with a speed of 12m/s slows down to 6m/s in 3s.The average acceleration of the bus is