Where does dust in the air come from?

Sources of dust in the air: soil particles; hair and skin of animals and people; microorganisms; substances during combustion; volcanic eruption; pollen; rocks and minerals; paper and fibers; cosmic dust; factories and other enterprises.

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.