An autogyro is a type of aircraft characterized by a free-spinning horizontal rotor that turns due to passage of air upward through the blades. Whereas a helicopter achieves lift with powered rotor blades that push air downward, an autogyro’s rotor is driven by aerodynamic forces alone. Invented by Spanish engineer Juan de la Cierva and first flown in 1923, the autogyro gained popularity before it was eclipsed by the more practical helicopter. What is the top speed reached by an autogyro? Discuss
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US Route 666

Renamed US Route 491 in 2003, US Route 666 was originally nicknamed “Devil’s Highway” because of the common Christian belief that 666 is the number of the beast. First commissioned in 1926, the route, which runs from New Mexico to Utah, was given its infamous name because it was the sixth spur along the highway’s parent US Route 66. Officials changed the name because its signs were among those most frequently stolen. What happened within days of the announcement that US 666 would be renumbered? Discuss
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Sadako Sasaki

Sadako Sasaki was only two years old when an atomic bomb destroyed her hometown of Hiroshima, Japan. A decade later, she was diagnosed with leukemia. Inspired by a Japanese legend that promises a wish to anyone who folds 1,000 origami cranes, Sadako began making paper cranes in the months before her death, completing 644 before losing her battle with cancer. She has since become a symbol of the impact of nuclear war, and schoolchildren around the world have learned her story through which books? Discuss
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Many children—usually under the age of 5—in overpopulated parts of the world suffer from kwashiorkor, a type of severe malnutrition. Commonly believed to be caused by protein deficiency, kwashiorkor is now thought by some to relate to bacterial contamination of grain ingested by newly weaned children. Symptoms include retarded growth, shifts in skin and hair pigmentation, abdominal swelling, immune deficiency, and liver damage. The term “kwashiorkor” is derived from a Ghanaian word meaning what? Discuss
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Hassan-i Sabbah

Sabbah was an 11th-century Muslim missionary who led a community of converts that settled in Alamut, a mountain fortress in what is now Iran, and became known as the Hashshashin, or Assassins. According to legend, Sabbah acquired Alamut by offering its owner 3,000 gold dinars for the amount of land that would fit in a buffalo’s hide. When the owner agreed, what did Sabbah do? Discuss
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