\displaystyle v^2=v_0^2+2as \Rightarrow (6\text{ m/s})^2=0^2+2a(3,6\text{ m}) \Rightarrow a=5\text{ m/s}^2 \displaystyle v=v_0+at \Rightarrow 6\text{ m/s} = (5\text{ m/s}^2)t \Rightarrow t=\frac{6}{5}\text{ s}
