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The horizontal fraction bar was introduced by the Arabs.
The first documented use of surgical anesthesia in the United States was in Connecticut in 1844.
Vaccines prevent between 2.5 and 4 million deaths every year.
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.
There are approximately 3 million unintended pregnancies in the United States each year.
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