A box of mass $40\;kg$ is placed on an open truck . The coefficient of friction between the box and the surface of the truck is $0.15$ with what maximum acceleration can the truck move so that the box does not slide out.

Question

$\begin{array}{1 1} 2\;m/s \\ 1\;m/s \\ 2.5\;m/s \\ 1.5\;m/s \end{array} $