The figures represent three cases of a ray passing through a prism of angle $A$. The case corresponding to minimum deviation is

$A$ light ray enters through a right-angled prism at point $P$ with an angle of incidence of $30^{\circ}$ as shown in the figure. It travels through the prism parallel to its base $BC$ and emerges along the face $AC$. The refractive index of the prism is:

$A$ glass prism deviates the red and violet rays through $9^{\circ}$ and $11^{\circ}$ respectively. $A$ second prism of equal angle deviates them through $11^{\circ}$ and $13^{\circ}$ respectively. The ratio of dispersive power of the second prism to the first prism is

$A$ parallel beam of monochromatic light is incident at one surface of an equilateral prism. The angle of incidence is $55^o$ and the angle of emergence is $46^o$. The angle of minimum deviation will be:

The ratio of the angle of minimum deviation produced by a thin prism $(\mu = 3/2)$ in air to that in a liquid of refractive index $9/7$ is:

As shown in the diagram, when the incident ray is parallel to the base of the prism, the emergent ray grazes along the second surface. If the refractive index of the material of the prism is $\sqrt{2}$, the angle $\theta$ of the prism is: (in $^{\circ}$)