What are some of the problems connected to a high population density, and its affects on the members of the population and the environment

preservation because he preserves part of the land and preserves means save

explanation:

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.