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Results 1 - 3 of 3 for cities
  1. Rural Health Concerns (National Library of Medicine)  
    Around 15% of people in the United States live in rural areas. There are many different reasons why you might choose to live in a rural community. You may want ...
  2. Air Pollution (National Library of Medicine)  
    ... is a major part of air pollution in cities. When ozone forms air pollution, it's also called ...
  3. Global Health (National Library of Medicine)  
    ... country's borders. With more people living in crowded cities and traveling to other countries, it's easier for ...