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The Romans did not use numerals to indicate fractions but instead used words to indicate parts of a whole.
Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
There are more sensory neurons in the tongue than in any other part of the body.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
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