Refractive indexes of two mediums are:

C id the center of curvature

Distance of C from the pole =20cm

Therefore, the radius of curvature R=20 cm

Distance of Source S from the pole is 25 cm.

Therefore, object distance u= -25

Image distance =v

⇒

⇒

The location of image is 100 cm from the pole and on the side of Source S.