Answer:
1. Decrease
2. Photosynthesis
3. Cellular respiration
Step-by-step explanation:
Photosynthesis in a plant requires light source to occur. The photosynthetic process gives oxygen gas (O2) as a waste product. This means that the production of oxygen is dependent on the intensity of light.
On the other hand, cellular respiration uses up or consumes oxygen in a plant. Hence, an increase in respiration reduces oxygen level if photosynthesis does not produce.
According to this question, If you move a plant further and further away from a light source, the level of O2 production would DECREASE because the process of PHOTOSYNTHESIS slows and the process of CELLULAR RESPIRATION speeds up.