The angle of polarisation for a medium is $60^o$. What will be the critical angle for this medium?

The angle of incidence of light falling on a material is $60^{\circ}$,and the reflected light is completely polarized. The speed of the refracted ray inside the material (in $m/s$) is:

For a given medium, the polarizing angle is $60^o$. What will be the critical angle for this medium?

Unpolarised red light is incident on the surface of a lake at an incident angle $\theta_{R}$. An observer seeing the light reflected from the water surface through a polariser notices that on rotating the polariser,the intensity of light drops to zero at a certain orientation. The red light is replaced by unpolarised blue light. The observer sees the same effect with reflected blue light at an incident angle $\theta_{B}$. Then,

When the angle of incidence is $60^{\circ}$ on the surface of a glass slab,it is found that the reflected ray is completely polarized. The velocity of light in glass is

The polarising angle for water is $53^\circ 4'$. If light is incident at this angle on the surface of water and reflected, the angle of refraction is: