Mi Ailin (1896— 1953) is a famous popular science writer, engineer and children's literature writer in the Soviet Union. Famous popular science works include 100,000 whys, What time is it now, black and white, the sun on the table, a trip in the atomic world, things around us and so on.

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Ilya's "100,000 Why", a book with strong vitality, is taken from Ilya's works, while Millin is taken from a sentence by Lu Kipling, an English writer who won Nobel Prize in Literature in 1907: "Where are the 5,000? How about the 7,000? Why are the 100,000?".