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The heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
The horizontal fraction bar was introduced by the Arabs.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
The average office desk has 400 times more bacteria on it than a toilet.
Everyone has one nostril that is larger than the other.
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