A particle is moving along a straight line with an initial velocity of $6\frac{m}{s}$ when it is

subjected to a deceleration of $a=-1\mathrm{.}5v^{\frac{1}{2}}\frac{m}{s^2},$ where $v$ is in $\frac{m}{s}.$ Determine how far it

travels before it stops. Include units and round your answer to $3$ sig figs.