The critical angle of a certain medium is ${\sin ^{ - 1}}\left( {\frac{3}{5}} \right)$. The polarization angle is

At what angle of incidence $i$ will the light reflected from water be completely plane-polarized (in $^\circ$)? (Given refractive index of water $\mu = 1.33$)

Given below are two statements:
Statement $I$: If the Brewster's angle for the light propagating from air to glass is $\theta_B$,then Brewster's angle for the light propagating from glass to air is $\frac{\pi}{2} - \theta_B$.
Statement $II$: The Brewster's angle for the light propagating from glass to air is $\tan^{-1}(\mu_g)$ where $\mu_g$ is the refractive index of glass.
In the light of the above statements,choose the correct answer from the options given below:

Unpolarised light is incident on the boundary between two dielectric media,whose dielectric constants are $2.8$ (medium $1$) and $6.8$ (medium $2$),respectively. To satisfy the condition that the reflected and refracted rays are perpendicular to each other,the angle of incidence should be $\tan ^{-1}\left(1+\frac{10}{\theta}\right)^{\frac{1}{2}}$. The value of $\theta$ is $.............$ (Given for dielectric media,$\mu_{r}=1$)

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

Consider a tank made of glass (refractive index $1.5$) with a thick bottom. It is filled with a liquid of refractive index $\mu$. $A$ student finds that,irrespective of what the incident angle $i$ (see figure) is for a beam of light entering the liquid,the light reflected from the liquid-glass interface is never completely polarized. For this to happen,the minimum value of $\mu$ is