In a 1961 speech, who said "Ask not what America will do for you, but what together we can do for the freedom of man"?

In 431 BC, Thucydides began writing the history of which war while he was fighting in it? Which pop artist's New York studio was known as The Factory? In a 1931 issue of The New Yorker, who quipped, "Theodore Dreiser should ought to write nicer"? In a 1947 novella by John Steinbeck, a diver named Kino finds which valuable title object to pay his child's doctor bil… In a 1985 book, which financier called arbitrage "Wall Street's best kept money-making secret"? In a 2002 blockbuster, who played both Peter Parker and "your friendly neighborhood Spider-Man"? In a leaf, which food-making process takes place in the palisade and spongy cells? In a legal case he's the equivalent of Mr. X; in real life, he was a member of the band X. Who is he?