How does the composition of the air in a closed room change during a lesson?

The volume fraction of oxygen decreases from 21% to 16%, the volume fraction of carbon dioxide increases from 0.03% to 4%, and water vapor also increases.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.