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The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
If you could remove all of your skin, it would weigh up to 5 pounds.
According to the CDC, approximately 31.7% of the U.S. population has high low-density lipoprotein (LDL) or "bad cholesterol" levels.
The familiar sounds of your heart are made by the heart's valves as they open and close.
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