Object O is placed at a distance of 14cm from an equi convex lens $L_1$ of refractive index $\mu =\frac{3}{2}$  and radius of curvature of lens surface is 32 cm. One of its surface is silvered another convex lens  $L_2$  of focal length 24 cm is placed between object and silvered lens such that the final image coincides with the object. The distance between object and the lens $L_2$  in cm is ……… ( Take first Refraction from Lens  $L_2$ )