Physics: light and refraction?

What distance does light travel in water, glass, and diamond during the time that it travels 1.0 m in vacuum? (t=3.3 ns) The refractive indices for water, glass, and diamond are 1.33, 1.50, and 2.42, respectively.

Fred2015-02-15T12:06:06Z

Speed of light in medium of refractive index, n, is
v = c/n

Distance, L, that light travels in time, t, is
L = ct

Distance, s, traveled through refractive index, n, in the same time that light in vacuum travels a distance, L, is
s = vt = ct/n = L/n

So just use L = 1 m, and the various n values, and those are your answers!