At the Oscars for 1942 films, which composer opened the envelope and announced himself as the Best Song winner for "White Christmas"?

As a navigator, which future Pacific explorer helped the British capture Quebec in 1759? As a newsboy on the Grand Trunk Railway in 1862, which future inventor published the first newspaper printed on a train? As a New York lawyer in the 1780s, Alexander Hamilton lived on which Manhattan street now synonymous with finance? Which nation annexed the Nigerian port of Lagos in 1861 as part of its 19th-century expansion? Which Mississippi native served as a White House spokesman under President Reagan in the 1980s? As a producer in 1997, who had several No. 1 hits, including his own "Can't Nobody Hold Me Down"? As a quarterback for the Oklahoma Sooners, which future GOP congressman was MVP of the 1980 and 1981 Orange Bowls? As a ratio, 7 is to 10 as what number is to 30?