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Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
Asthma cases in Americans are about 75% higher today than they were in 1980.
There are 60,000 miles of blood vessels in every adult human.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
The horizontal fraction bar was introduced by the Arabs.
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