Bottom of glass beaker is made of a thin equi-convex lens having bottom side silver polished as shown in the figure. Now the water is filled in the beaker upto a height of h = 4 m. The image of point object floating at middle point of beaker at the surface of water coincides with it. The value of radius of curvature of lens (in m) is $({\mathrm{\mu }}_{\mathrm{g}}=\frac{3}{2},{\mathrm{\mu }}_{\mathrm{w}}=\frac{4}{3})$