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Blood is approximately twice as thick as water because of the cells and other components found in it.
There are more sensory neurons in the tongue than in any other part of the body.
The horizontal fraction bar was introduced by the Arabs.
The average office desk has 400 times more bacteria on it than a toilet.
Egg cells are about the size of a grain of sand. They are formed inside of a female's ovaries before she is even born.
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