| A | B |
|---|
| contiguous | referring to areas that touch or share a boundary |
| urban | related to a city or densely populated area |
| megalopolis | area in which neighboring urban areas blend into one "super city" |
| rural | relating to the countryside, not the city |
| coral reef | low-lying ocean ridge made of coral |
| free enterprise system | basis of a market economy in which people start and run businesses to make a profit with little government intervention |
| service industry | business that provides services to people rather than producing goods |
| farm belt | region of the midwestern United States with flat land and fertile soil |
| dry farming | method of wheat farming in dry areas that conserves moisture by deep plowing |
| acid rain | precipitation in which water carries large amounts of chemicals, especially sulfuric acid |
| interdependent | referring to countries or people that rely on one another |
| immigrant | person who moves from one place to make a permanent home in another |
| colony | overseas settlement made by a parent country |
| revolution | for a planet, one complete trip around the sun; in politics, a sudden radical change in government |
| republic | government without a monarch, in which people elect important officials |
| multicultural | referring to something that includes many different cultures |
| ethnic group | people who share a common cultural background, including ancestry and language |
| mobile | moving from place to place |
| national park | public lands set aside for recreation and wilderness |
