From the 1930s to 1970, millions of American children learned to read with books featuring which brother and sister and their dog, Spot?

Between 1903 and 1905, which Norwegian explorer located the North Magnetic Pole during his voyage through the Northwest… Between 1913 and 1932, Canada built a new, deeper Welland Canal to connect which two Great Lakes? Between 1919 and 1925, which sculptor made several marble and bronze versions of "Bird in Space"? Between 1921 and 1951, the Chicago Cubs held spring training on which island near Los Angeles, owned by the Wrigley fam… Between 1937 and 1950, which boxer fought in 27 heavyweight title fights, winning 26? Between 1951 and 1977, which foundation, endowed by a car-making family, gave hundreds of millions of dollars to public… Between 1955 and 1982, a good polka was often featured on which bandleader's "wunnerful" TV program? From 1960 to 1975, Madagascar was officially known by what name?