A convex lens of focal length 20 cm is placed glass slab of refractive index $\large\frac{3}{2}$.A parallel beam of light is incident on the convex lens. The light will converge.

Question

(a)at a distance of 15 cm from lens

(b)at a distance of 25 cm from lens

(c)at a distance of 20 cm from lens

(d)at a distance of 30 cm from lens