The refractive index $(R.I.)$ of a prism is $\sqrt{\frac{7}{3}}$ and the angle of the prism is $60^{\circ}$. The limiting angle of incidence of a ray that will be transmitted through the prism is .....$^{\circ}$

Consider the following statements for the refraction of light through a prism,when the angle of deviation is minimum.
$(A)$ The refracted ray inside the prism becomes parallel to the base.
$(B)$ Larger angle prisms provide smaller angle of minimum deviation.
$(C)$ The angle of incidence and the angle of emergence become equal.
$(D)$ There are always two sets of angles of incidence for which the deviation will be the same,except at the minimum deviation setting.
$(E)$ The angle of refraction becomes double the prism angle.
Choose the correct answer from the options given below.

$A$ ray of light is incident normally on a prism of refractive index $1.5$,as shown. The prism is immersed in a liquid of refractive index $\mu$. The largest value of the angle $ACB$ such that the ray is totally internally reflected at the face $AC$ is $30^o$. Then the value of $\mu$ must be :

$A$ graph is plotted between angle of deviation $(\delta)$ and angle of incidence $(i)$ for a prism. The nearly correct graph is

$A$ light ray incident normally on one face of an equilateral prism and emerges out grazingly at the other face. The refractive index of the prism is

For a prism of apex angle $45^o$,it is found that the angle of emergence is $45^o$ for grazing incidence. Calculate the refractive index of the prism.