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The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
If all the neurons in the human body were lined up, they would stretch more than 600 miles.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Illicit drug use costs the United States approximately $181 billion every year.
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