A group of students studied the effect of light intensity on the rate of transpiration. They moved a light source to different distances from the potometer and at each distance measured the distance the air bubble moved in a set time. What is the purpose of this experiment?
1) To determine the relationship between light intensity and the rate of transpiration
2) To measure the distance the air bubble moved in a set time
3) To study the effect of distance on the rate of transpiration
4) To compare the rate of transpiration at different light intensities