1. [2 pts] Give an example of an equation for a generalized cylinder.

2. [2 pts] Give an example of an equation for a surface of revolution.

3. [3 pts] Give an example of an equation for a quadric surface that is neither a generalized cylinder nor a surface of revolution.

4. [3 pts] Write down a parameterization of the circle x^2 + y^2 = 1.