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Vaccines prevent between 2.5 and 4 million deaths every year.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
The average office desk has 400 times more bacteria on it than a toilet.
Excessive alcohol use costs the country approximately $235 billion every year.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
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