According to an old proverb, what knocks only once?

An offshoot of the Salem colony, which city was founded on September 17, 1630, by John Winthrop and other Puritans? A museum in Ogdensburg, New York, is devoted to which artist, creator of the 1895 sculpture "The Bronco Buster"? Which name, from the Spanish for "double", was given to an old Spanish gold coin? An old proverb says that many what make light work? An old satellite brings Clint Eastwood's retired engineer back into service in which 2000 film? An old stuffed bear from which German company, known for the button in its toys' ears, fetched a huge sum at auction in… Which old nickname for the American South may come from a $10 bank note printed in New Orleans? Which American figure skater won Olympic gold at Albertville in 1992?