Mix a tablespoon of milk powder and river sand. Pour the mixture into a glass of water. To completely “drown” the sand, tap on the outer wall of the glass with a spoon. Which of the components of the mixture remained on the surface of the water?
Powdered milk. Small particles of milk powder are poorly wetted by water and therefore are retained on its surface – they float.
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.