Please Help! A car traveling at 15 m/s starts to decelerate steadily. It comes to a complete stop in 10 seconds. What is it's acceleration?

Answer:
initial velocity = 15 m/s
final velicity = 0 m/s
time required = 10sec
Formula is V = U + at
0 = 15 + a 10
-15 ÷ 10 = acc
acc = - 1.5 m/s^2
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