More than a dozen men have stood on the surface of the moon, but only three have been to Challenger Deep in the Marianas Trench, the deepest known spot in the ocean.
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Connecticut and Rhode Island never ratified the 18th Amendment (Prohibition).
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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The Amazon rainforest produces more than 20% the world's oxygen supply.
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The Caspian Sea is also classed as the world's largest lake.
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