Two cars with the same speed $v$ have constant decelerations of $a_{1}$ and $a_{2}\left(a_{1}<a_{2}\right)$ respectively at a point on the road. If they are travelling in the same direction on parallel roads, the difference in times in which they reach their destinations (where they stop moving), is
(a) $\mathrm{v}\left(\frac{1}{\mathrm{a}_{1}}-\frac{1}{\mathrm{a}_{2}}\right)$
(b) $\mathrm{v}\left(\frac{1}{\mathrm{a}_{1}}+\frac{1}{\mathrm{a}_{2}}\right)$
(c) $\frac{\mathrm{v}}{2}\left(\frac{1}{\mathrm{a}_{1}}-\frac{1}{\mathrm{a}_{2}}\right)$
(d) $\frac{1}{2}\left(\frac{v}{a_{1}-a_{2}}\right)$