7. A ray of light is travelling through air, with refractive index 1.00, and then enters a block of glass, with refractive index 1.52. The light ray enters the glass perpendicular to its surface. (a) Does the light bend as it enters the glass? Justify your response (briefly). (b) What is the speed of light once it is in the glass? The glass block is now rotated so that the light ray enters at an angle of 15° from the normal. (c) Use Snell's law to calculate the angle of the light ray inside the glass. (d) Sketch the light ray entering the glass block, being sure to include the normal on your diagram.[1 mark]