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The horizontal fraction bar was introduced by the Arabs.
On average, someone in the United States has a stroke about every 40 seconds. This is about 795,000 people per year.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Approximately 15–25% of recognized pregnancies end in miscarriage. However, many miscarriages often occur before a woman even knows she is pregnant.
The familiar sounds of your heart are made by the heart's valves as they open and close.
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