Correct Answer - d.
Distance of image from the plane surface is as follows:
`x_(1)=(4)/(1.6)`
`=2.5cm(d_(app)=(d_(actual))/(mu))`
For the curved side
`(1.6)/(4)+(1)/(x_(1))=(1-1.6)/(8)`
`:. x_(2)~~-3.0cm`
The minus sign means the image is on the object side.
`:. I_(1)I_(2)=(8-2.5-3.0)cm=2.5cm`