i think this is the incomplete page that you are showing but the answer is
:-
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B</u></h2>
Use the definition of acceleration:
Acceleration = (change of velocity) divided by (time for the change)
The graph says:
Change of velocity = -6 m/s
Time for the change = 3 sec
So Acceleration = (-6m/s) / (3 s)
That's -6/3 m/s•s
or
-2 m/s^2
Answer:
Explanation:
Given
mass of boy 
mass of girl 
speed of girl after push 
Suppose speed of boy after push is 
initially momentum of system is zero so final momentum is also zero because momentum is conserved




i.e. velocity of boy is 2.82 m/s towards west