In the given figure,what is the angle of the prism?

$A$ ray of light passing through an equilateral prism has a velocity of $2.12 \times 10^8 \text{ m/s}$ in the prism material. The minimum angle of deviation is . . . . . . degrees.

The angle of a prism is $30^o$ and its refractive index is $\sqrt{2}$. One of its surfaces is silvered. At what angle of incidence should a ray be incident on the other surface so that after reflection from the silvered surface,it retraces its path?

$A$ prism with a refractive index of $1.53$ is placed in water with a refractive index of $1.33$. If the angle of the prism is $60^{\circ}$,then the angle of minimum deviation in water will be ....$^{\circ}$.

$A$ prism has a refracting angle $A$. The second refracting surface of the prism is silvered. $A$ light ray falling on the first refracting surface with an angle of incidence $2A$ reaches the second surface and returns back along the same path due to reflection at the silvered surface. The refractive index of the material of the prism is:

$A$ plane polarized blue light ray is incident on a prism such that there is no reflection from the surface of the prism. The angle of deviation of the emergent ray is $\delta=60^{\circ}$ (see Figure-$1$). The angle of minimum deviation for red light from the same prism is $\delta_{\text{min}}=30^{\circ}$ (see Figure-$2$). The refractive index of the prism material for blue light is $\sqrt{3}$. Which of the following statement$(s)$ is(are) correct?
$(A)$ The blue light is polarized in the plane of incidence.
$(B)$ The angle of the prism is $60^{\circ}$.
$(C)$ The refractive index of the material of the prism for red light is $\sqrt{2}$.
$(D)$ The angle of refraction for blue light in air at the exit plane of the prism is $60^{\circ}$.