A photic sneeze is triggered by what?

A. Philip Randolph, who first proposed a march on which city in 1941, also helped organize the one in 1963? A Philippine one-peso coin of 1947 depicted which American as "Defender and Liberator"? A phillumenist collects items related to which smoking aids? Which philosopher and student of Plato lived from 384 to 322 B.C.? Where does a photographer go "to see what develops"? A phrase in Longfellow's "Paul Revere's Ride" gave its title to which 1996 Sandra Bullock film? Which physician, educated partly in Hawaii, led the movement that overthrew the Qing (Manchu) dynasty in 1911? Which physicist, reflecting on the atomic bomb, reportedly said in 1955, "If only I had known, I would have become a wa…