In an experiment on tracing the path of a ray of light through a rectangular glass slab, four students A, B, C and D used the following values of the angle of incidence and the distance between the feet of the two pins (fixed on the incident rays) :

In an experiment on tracing the path of a ray of light through a recta

1.	In an experiment on tracing the path of a ray of light through a rectangular glass slab, four students A, B, C and D used the following values of the angle of incidence and the distance between the feet of the two pins (fixed on the incident rays) :
Answer» `30^(@), 45^(@), 60^(@)` and 1 cm `30^(@), 45^(@), 60^(@)` and 6 cm `20^(@), 50^(@), 80^(@)` and 10 cm `20^(@), 50^(@), 80^(@)` and 15 cm Solution :NA