31. A researcher gathers data showing that people who are taller than average are also heavier than average. Indicate which of the following is (are) a possible graphical representation(s) of this correlation. (The vertical axis represents height and the horizontal axis represents weight. On both axes, values increase with distance from the origin.)

32. Mark all models(s) that are consistent with the information in the following graph. (That is, mark an answer if it cannot be ruled out using the information in the following graph.) Assume you have no data other than what is presented in this graph.

33. Circle all of the following models that are consistent with the following graph. (Note: "consistent with" means "cannot be ruled out using"). None, one, or more than one answer may apply.

34. Which of the following statements provide an example of (describe) causation?

35. Mark all of the following models that can be rejected by the information in the following paragraph.

Most electric utility companies are privately owned. However, in a few cities, such as Austin, the electric services are provided not by a private company, but by a publicly owned company. On average, privately owned utility companies charge 8.8 cents per kilowatt hour for electricity, while publicly owned utilities charge 6.8 cents per kilowatt hour.

Which models can be rejected?