Answers

2015-06-01T20:22:53+05:30
It will be done by using the first equation of motion 

v=u+a*t
v=72 km/hr= 20 m/s 
u=36 km/h= 10 m/s
t= 5 s
v=u+a*t
20=10+a*5
20-10=5a
10=5a
a=10/5
a=2 m/s²
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