NEED AWNSER NOW! WILL MARK BRAINLY! Which term is defined as the ratio of the speed of light in a vacuum to the speed of light in the material it is passing through?

index of reflection

index of refraction

angle of reflection

angle of incidence

NEED AWNSER NOW WILL MARK BRAINLY Which term is defined as the ratio of the speed of light in a vacuum to the speed of light in the material it is passing throu class=