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Vaccines prevent between 2.5 and 4 million deaths every year.
The horizontal fraction bar was introduced by the Arabs.
There are more bacteria in your mouth than there are people in the world.
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
Approximately 15–25% of recognized pregnancies end in miscarriage. However, many miscarriages often occur before a woman even knows she is pregnant.
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