A prism works because the different colors of light travel at different speeds inside the glass. ... This is because what is called the index of refraction, (the ratio of the speed of light in a vacuum to the speed of light in a material), is increased for the slower moving waves (i.e. violet).
A. Moderate. If he can carry on a conversation without running out of breath then he is probably not a stranger to that type of workout and is use to much harder tasks.
