Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
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The Sun and Moon appear to be the same size because the moon is 400 times smaller than the Sun, but 400 times closer to Earth.
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The world’s smallest book, “Teeny Ted from Turnip Town”, is 100×70 micrometers in size and requires a scanning electron microscope to read, as light beams are too large.
6