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The horizontal fraction bar was introduced by the Arabs.
The immune system needs 9.5 hours of sleep in total darkness to recharge completely.
The calories found in one piece of cherry cheesecake could light a 60-watt light bulb for 1.5 hours.
Signs and symptoms of a drug overdose include losing consciousness, fever or sweating, breathing problems, abnormal pulse, and changes in skin color.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
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