Explanation:
Wooho Physics my favorite subject! And my 100th answer :)
We will use the formula
[tex]\boxed{\tt{ Acceleration = \dfrac{v - u}{t}}}[/tex]
In this question :-
Applying the formula:-
[tex]\sf{ Acceleration = \dfrac{6 - 4}{5}}[/tex]
[tex]\sf{ Acceleration = \dfrac{2}{5}}[/tex]
So, Acceleration is 0.4 m/s² is the answer.
Hope it helps :)