What is the angle of polarisation?

What is angle of polarisation and obtain the equation for angle of polarisaition.

From Brewster's law of polarisation, it follows that the angle of polarisation depends upon

A ray of light in air is incident on a glass plate at polarising angle of incidence. It suffers a deviations of 22^(@) on entering glass. The angle of polarisation is

If the polarising angle for air glass interface is 57^(@) , what is the angle of refraction in glass ?