Given
time (t) = 5 seconds
Initial speed (u) = 80 km/hr = 22.2222m/s
final speed (v) = 0 km/hr =0m/s
Note I change to m/s so as to be consistent with units
formula: V=U+at where a is acceleration
0=22.2222+5a
a=22.2222/5
acceleration = 4.44444 m/s^2
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