what environmental variables might affect the net rate of photosynthesis? list at least two. why do you think they would affect it? how do you predict they would affect it? 3. what features or variables of the plant leaves might affect the net rate of photosynthesis? how and why? 4. could the way you perform the procedure affect the outcome? of the outcome changes, does it mean the net rate of photosynthesis has changed? why do you think that?