Could somebody give me an example by at least showing me how to do one of these problems that is in the attachment

Look at the following graph of the given equation. determine whether the equation is a function. explain why or why not.

When you are making a circle graph by hand, how do you convert a number for a part into its corresponding angle measure in the circle graph? when you are making a circle graph by hand, what should you do if one of your angle measures is greater than 180°?

Either enter an exact answer in terms of \piπ or use 3.143.14 for \piπ and enter your answer as a decimal.