Two students design an experiment to see if pushing or pulling a box across the floor is more effective. the first student pushes the box across the floor a distance of 20 feet and the second student times how long it takes. next they switch roles and the second student pulls the same box across the floor instead of pushing. they repeat this 5 times. which statement best describes the design of this experiment? a) this is a well design experiment. b) this experiment is not well design because 20 feet is too long a distance. c) this experiment is not well design because they should not repeat it 5 times. d) this experiment is not well design because they should not switch roles during the experiment.