\"\"

\

Index of refraction of light in passing from a vacuum into glass is \"\".

\

Angle of incidence \"\".

\

The law of snell is \"\".

\

Substitute \"\" and \"\".

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\"

\

\"\".

\

\"\"

\

The refraction angle is \"\".