If you open a bottle of perfume, then soon their smell will spread throughout the room, but at the same time we will not notice a decrease in the volume of perfume in the bottle. Explain this phenomenon.
When the bottle is opened, some of the molecules mix with air molecules, and we smell the perfume. But since the size of the molecules is very small, the volume of the perfume is practically.
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.