Check the possible extraneous variable(s) in the following study: Researchers want to determine whether time of day and caffeine consumption influences test performance, they ask half of the students in a Research Methods class to take exam 1 at 10:00am and the other half of the students to take the exam at 6:00pm, within each of these groups half of the students drink coffee before the exam and the other half drinks water instead. (check all that apply)