Solids have a definite mass, a definite shape, and a definite volume. They are not compressible and are the most tightly packed together.
Liquids have definite mass and definite volume. Liquids take up the shape of the container and are not compressible. They are slightly packed together but are allowed to move freely.
In heavily deforested areas, soil erosion and nutrient runoff are common after a rainfall. Soil erosion tends to be greater in drier, more mountainous areas, where there is less vegetation to prevent the movement of soil and to absorb the nutrients