Snell's law is a formula used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different isotropic media, such as water, glass, or air.
in a class, 30 like football, 60 like cricket, 40 like hockey, 5 like football and cricket, 7 like hockey and football, 10 like cricket and hockey, 4 like all 3 games, and 6 like no games. find the no. of students in the class.
[ch- sets, class 11]