$A$ glass slab is placed over a page on which the word $VIBGYOR$ is printed with each letter in its corresponding colour. $(i)$ Will the image of all the letters be in the same place? $(ii)$ If not, state which letter will be raised to the maximum. Give a reason for your answer.

$(i)$ No, the images of letters of different colours will be raised by slightly different heights.
$(ii)$ The letter $V$, corresponding to the violet colour, will be raised to the maximum. This is because the apparent depth is given by the formula: $\text{Apparent depth} = \frac{\text{Real depth}}{n}$. Since the refractive index $n$ is maximum for the violet colour, its apparent depth will be the least. Consequently, the shift (raised height) is maximum for the violet colour.