1. (10 pts) Look at Figures 6.37 and 6.38 on pages 310 and 311 of the textbook. Write 50-100 words on why they look different.
2. (10 pts) Look at Figure 6.39 on page 314 of the textbook. What is it about the spheres that the global model looks different from the local?
3. (10 pts) Consider the sphere \(x^2+y^2+z^2=169\). What is the normal to the sphere at the point (-12,3,-4)? Be sure your normal is normalized.
4. (10 pts) Consider a block of glass with index of refraction 1.5. Some light is shining straight down on it. This is called normal incidence. How much of the light reflects off the glass and how much transmits into the glass? Hint: Use Fresnel's law.
5. (10 pts) A small light source that is twice as far away is 1/4 as bright. That is, there is an inverse square fall off for brightness. However, when modeling light in graphics, we usually don't do that. Why?

(Total: 50 points.)