Question

what process do plants use to absorb co₂ and release o₂?
○ transpiration
○ respiration
○ condensation
○ photosynthesis
question 4
what happens to air pressure as altitude increases?
○ it increases
○ it decreases
○ it fluctuates randomly
○ it stays the same

Explanation:

1. For the first question: Photosynthesis is the biological process where plants take in $\text{CO}_2$, use sunlight, water, and chlorophyll to produce glucose, and release $\text{O}_2$ as a byproduct. Transpiration is water loss via leaves, respiration is the opposite gas exchange, and condensation is a water cycle phase unrelated to this plant gas exchange.
2. For Question 4: Air pressure depends on the weight of the air column above a point. As altitude rises, the height of this air column shrinks, so the pressure exerted by the air decreases.

Answer:

1. Photosynthesis
2. It decreases