Inspired by the example about how background music influences choice of entre at a restaurant, a statistics student decided to investigate other ways to influence a person's behavior. Using 60 volunteers, she randomly assigned 20 volunteers to get a "red" survey, 20 volunteers to get a "blue" survey, and 20 volunteers to get a control survey. The first three questions on each survey were the same, but the fourth and fifth questions were different. For example, the fourth question on the "red" survey was "When you think of the color red, what do you think about?" On the blue survey, the question replaced red with blue. On the control survey, the last two questions were not about color. As a reward, each volunteer was allowed to choose a chocolate candy in a red wrapper or a chocolate candy in a blue wrapper. The table shows the result of the experiment