Problem: There is confusion currently as to the name of the eldest Vinaccia luthier who first ran the shop. His name has been put forth as Gennaro Vinaccia (active c. 1710 to c. 1788) and Nic. Vinaccia. His son Antonio Vinaccia was active c. 1734 to c. 1796. An early extant example of a mandolin is one built by Antonio Vinaccia in 1759, which resides at the University of Edinburgh. Another is by Giuseppe Vinaccia, built in 1893, is also at the University of Edinburgh. The earliest extant mandolin was built in 1744 by Antonio's son, Gaetano Vinaccia. It resides in the Conservatoire Royal de Musique in Brussels, Belgium.
Who built the earliest mandolin in 1474?
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Answer: unanswerable

Problem: The London Natural History Society suggest that London is "one of the World's Greenest Cities" with more than 40 percent green space or open water. They indicate that 2000 species of flowering plant have been found growing there and that the tidal Thames supports 120 species of fish. They also state that over 60 species of bird nest in central London and that their members have recorded 47 species of butterfly, 1173 moths and more than 270 kinds of spider around London. London's wetland areas support nationally important populations of many water birds. London has 38 Sites of Special Scientific Interest (SSSIs), two National Nature Reserves and 76 Local Nature Reserves.
The London Natural History Society has document how many species of butterfly?
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Answer: 47

Problem: The world's first commercial broadcast automation audio compression system was developed by Oscar Bonello, an engineering professor at the University of Buenos Aires. In 1983, using the psychoacoustic principle of the masking of critical bands first published in 1967, he started developing a practical application based on the recently developed IBM PC computer, and the broadcast automation system was launched in 1987 under the name Audicom. Twenty years later, almost all the radio stations in the world were using similar technology manufactured by a number of companies.
Who developed the first commercial broadcast automation band?
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Answer:
unanswerable