A small object is at the bottom of a container which has water filled up to a height of 20 cm. There is a plane mirror inclined at `45°` to the horizontal above the container. A convex lens having focal length 15 cm is at a distance of 50 cm from the mirror. The horizontal principal axis of the lens is at a distance of 45 cm from the bottom of the container. Find the distance of the image (from the lens) of the object as seen by an observer to the left of the lens. Light rays from the object hit the lens only after they are reflected from the mirror. (use `mu_("water") = 4//3)`

Answer

18 cm