Which of the following is an example of an experimental factorial design with two manipulated factors?
a researcher observed response times to an emergency among different response teams (police, firefighter) in two different cities.
a researcher observes the life satisfaction scores of different types of athletes (club, varsity) from different types of schools (Division I, II, III schools)
a researcher compares attendance records for male and female college students with different living arrangements (on-campus, off-campus)
a researcher randomly assigns participants to consume popcorn (fresh, stale) during a movie clip that was played at a soft or loud volume
