Can absolute refractive index of a medium exceed unity?

Absolute refractive index of vaccum is

What is the refractive index of a medium?

Define absolute refractive index.

Can the value of absolute refractive index of a medium be less than 1?

Can the value of absolute refractive index of a medium be less than 1?

If the absolute refractive index of a medium is sqrt2 , calculate the critical angle of glass to the medium. Given that the critical angle of glass to air is 30^(@) .

Can relative refractive index of a medium with respect to another be less than unity?

On what factors does the refractive index of a medium depend?

Value of absolute refractive index of medium A,B,C and D are 1.5,1.4,2.5 and 1.3. In which medium velocity of light is higher-

How does the refractive index of a medium depend on the velocity of light?