1 e. Plss

Dear Student ,
From the definition of acceleration , 
the time rate of change in velocity is called acceleration.
So , $$\begin{gathered} acce{l}^n=\frac{change in velocity}{time} \\ 5=\frac{change in velocity}{2} \\ change in velocity = 10m/s \end{gathered}$$

Hope this helps you . 

Regards