6. Can pleasant aromas help a student learn better? Two researchers believed that the presence of a floral scent could improve a person's learning ability in certain situations. They had ten people work through a pencil-and-paper maze two times, first wearing an unscented mask and then wearing a scented mask. Tests measured the length of time it took subjects to complete each of the two trials. They reported that, on average, subjects wearing the floral- scented mask completed the maze more quickly than those wearing the unscented mask. a. Is this an observational study or experiment? Explain. b. Identify the response and explanatory variables. c. Explain how confounding makes the results of this study worthless.