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The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Drying your hands with a paper towel will reduce the bacterial count on your hands by 45–60%.
Vaccines prevent between 2.5 and 4 million deaths every year.
Green tea is able to stop the scent of garlic or onion from causing bad breath.
The longest a person has survived after a heart transplant is 24 years.
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