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Vaccines prevent between 2.5 and 4 million deaths every year.
Cyanide works by making the human body unable to use oxygen.
About 100 new prescription or over-the-counter drugs come into the U.S. market every year.
In 1844, Charles Goodyear obtained the first patent for a rubber condom.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
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