I think the veins absorb the photons because they're located at the top part of a leaf while the stomata that serves as the leaf's lungs are found at the under side.
The answer is 60% are active
The answer is d. all of the above. The amount of nitrogen in the atmosphere can be affected by the inorganic nitrogen fertilizers, sewage treatment plants and pollution coming from factories. Hope this is the answer and this would be of help.
