A plano-convex lens is made ofa material of refractive index n. When a smallobject is placed 30 cm awayin front of the curved surface of the lens, an image of double the size of the object is produced. Dueto reflection from the convex surface of the lens, another faint image is observed at a distance of 10 cm away from the lens. Which of the following statement(s)
is(are) true?

A

The refractive index of the lens is 2.5

B

The radius of curvature of the convex surface is 45 cm

C

The faint image is erect and real

D

The focal length of the lens is 20 cm