State the laws of refraction of light. Explain the term absolute refractive index of a medium and write an expression to relate it with the speed of light in vacuum.                            

The absolute refractive indices of two media 'A' and 'B' are 2.0 and 1.5 respectively. If the speed of light in medium 'B' is 2x108 m/s, calculate the speed of light in : (i) vacuum, (ii) medium 'A'           (5 Marks)