Calculate the angle of incidence if the angle of refraction is 30° in a medium of critical angle 45°

Kinetic energy = 1/2mv^2. since the mass is constant we can form a ratio of it's kinetic energy at 60 divided by that at 30 to see ke(60)/ke(30) = +(60^2)/30^2). this may be said to 300% increase.

Depotion can i think

I’m good with pshycology

Ithink it is letter b, i may be wrong but i think that is the answer