In 2003, which energy source produced about 20 percent of U.S. electricity at plants like Palo Verde in Arizona?

The U.S. Air Force's Project Blue Book, which ran from 1952 to 1969, investigated reports of what? By 1970, which former Harvard lecturer and 1960s psychedelic guru was on the run and living in Algeria? By the 1976 Olympics, which muscle-building drugs had been banned for Olympic competitors? By 1980, a global vaccination effort had eradicated which disease, the first human disease ever wiped out? In 1924, the Kansas City Monarchs won the first Negro League version of which championship, 5 games to 4? According to a 1782 explanation of the Great Seal, which three colors stand for valor, purity and vigilance? In 1948, the UN General Assembly adopted, with no votes against, a Universal Declaration of what? By an act of Congress in 1954, Armistice Day was renamed what?