A rectangular block of glass is placed on a mark made on the surface of the table and viewed from the vertical position of the eye. If the refractive index of glass is μ and its thickness is d, then the mark will appear to be raised up by-
1
\(\frac{(\mu +1)d}{\mu}\)
2
\(\frac{(\mu -1)d}{\mu}\)
3
\(\frac{(\mu +1)}{\mu d}\)
4
\(\frac{(\mu +1)\mu}{d}\)