James had a fixation on how to best preserve fresh cut flowers. He tried various methods: adding bleach to the water, using filtered water, adding an aspirin tablet to the water, using a combination of sugar and water, using cold water, and using hot water. Over the course of his study, he came to the conclusion that while bleach changed the color of the plant, it did allow for the plant to last longer than the other changes. Based on this study, the dependent variable is: 1. Type of plant 2. Life of the cut plant 3. Color of the plant 4. Changes to the water