The angle of a prism is $A$. One of its refracting surfaces is silvered. Light rays falling at an angle of incidence $2A$ on the first surface return back through the same path after suffering reflection at the silvered surface. The refractive index $\mu$ of the prism is

$A$ ray of light passes through an equilateral glass prism in such a manner that the angle of incidence is equal to the angle of emergence and each of these angles is equal to $\frac{3}{4}$ of the angle of the prism. The angle of deviation is (in $^{\circ}$)

Assertion: There exist two angles of incidence for the same magnitude of deviation (except for minimum deviation) by a prism kept in air.
Reason: In a prism kept in air,a ray is incident on the first surface and emerges out of the second surface. If another ray is incident on the second surface along the path of the previous emergent ray,then this ray emerges out of the first surface along the path of the previous incident ray. This principle is called the principle of reversibility of light.

$A$ prism is made of glass having a refractive index of $\sqrt{2}$. If the angle of minimum deviation is equal to the angle of the prism, then the angle of the prism is: (in $^{\circ}$)

At the condition of minimum deviation,the angle of emergence is .......

What is the maximum value of the refractive index of the material of a prism with prism angle $A$ such that light can pass through it?