When light travels from one medium to the other of which the refractive index is different, then which of the following will change

When light travels from one medium to the other medium of which the refractive index is different, then which of the following will change?

When a light ray travels from one medium to another with the same refractive index,

When a ray of light passes from air medium to denser medium then the refractive index is

When light travels from one medium to another of different density there is no change in

When light passes from one medium to other medium then the frequency of light

When light is refracted which of the following does not change?

When light is refracted which of the following does not change?