A ray of light travels from a medium of refractive index $$ \mu $$ to air . Its angle of incidence in the medium is $$ \theta $$ , measured from the normal to the boundary and its angle of deviation is $$ \delta $$ with the angle of refraction $$ \phi $$. A graph is plotted between $$ \delta $$ and $$ \theta $$ which is shown in the figure. Choose the correct relation from the following