Alexander Khalifman, Anatoly Karpov and Garry Kasparov have all been world champions at what?

Czar Alexander I entered which foreign capital in triumph in March 1814? Alexander I, czar during Napoleon's 1812 invasion of Russia, belonged to which dynasty? In 1237, the Treaty of York, signed by Alexander II and Henry III, fixed a lasting border between which two kingdoms? Alexander II was called the "Czar Liberator" for freeing which Russian laborers in 1861? Complete the title of Alexander McCall Smith's 1998 novel: "The No. 1 ___' Detective Agency". Which early plastic did Alexander Parkes develop in the 1850s? Complete Alexander Pope's line: "For fools rush in where angels ___." Alexander Pope wrote that "hope springs eternal in" what?