MEDICINE
INFECTIOUS DISEASES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Animals living close to people
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Lack of a water source (desert conditions)
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Wells that are not dug deep enough
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Aqueducts were not built high enough
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Detailed explanation-1: -The main point source of pollution to water is from sewage and waste water treatment, while for diffuse pollution, main sources are from farming and fossil fuel power plants (via the air).
Detailed explanation-2: -Germs and chemicals can get in drinking water at the water’s source or in the distribution system after the water has already been treated. Harmful germs and chemicals can get in the water from many sources, including: Fertilizers, pesticides, or other chemicals that have been applied to land near the water.
Detailed explanation-3: -Nutrient pollution, which includes nitrates and phosphates, is the leading type of contamination in these freshwater sources. While plants and animals need these nutrients to grow, they have become a major pollutant due to farm waste and fertilizer runoff.
Detailed explanation-4: -Before, when people lived as hunters/ collectors, river water was applied for drinking water purposes. When people permanently stayed in one place for a long period of time, this was usually near a river or lake. When there were no rivers or lakes in an area, people used groundwater for drinking water purposes.