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In 1872, Russian Alexander Lodygin invented an incandescent light bulb and obtained a Russian patent in 1874. He used as a burner two carbon rods of diminished section in a glass receiver, hermetically sealed, and filled with nitrogen, electrically arranged so that the current could be passed to the second carbon when the first had been consumed. Later he lived in the USA, changed his name to Alexander de Lodyguine and applied and obtained patents for incandescent lamps having chromium, iridium, rhodium, ruthenium, osmium, molybdenum and tungsten filaments, and a bulb using a molybdenum filament was demonstrated at the world fair of 1900 in Paris.
Who did not demonstrate at the world fair in 1900 in Paris?
A: unanswerable

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Congo's democratic progress was derailed in 1997 when Lissouba and Sassou started to fight for power in the civil war. As presidential elections scheduled for July 1997 approached, tensions between the Lissouba and Sassou camps mounted. On June 5, President Lissouba's government forces surrounded Sassou's compound in Brazzaville and Sassou ordered members of his private militia (known as "Cobras") to resist. Thus began a four-month conflict that destroyed or damaged much of Brazzaville and caused tens of thousands of civilian deaths. In early October, the Angolan socialist regime began an invasion of Congo to install Sassou in power. In mid-October, the Lissouba government fell. Soon thereafter, Sassou declared himself president.
In what month did Sassou regain the presidency?
A: October

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In 2012, Fortune ranked IBM the second largest U.S. firm in terms of number of employees (435,000 worldwide), the fourth largest in terms of market capitalization, the ninth most profitable, and the nineteenth largest firm in terms of revenue. Globally, the company was ranked the 31st largest in terms of revenue by Forbes for 2011. Other rankings for 2011/2012 include 1 company for leaders (Fortune), 1 green company in the United States (Newsweek), 2 best global brand (Interbrand), 2 most respected company (Barron's), 5 most admired company (Fortune), and 18 most innovative company (Fast Company).
In 2012 Fortune ranked the largest US firms by number employees, what was IBMs rank?
A: second largest

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During the 19th and 20th century, many national political parties organized themselves into international organizations along similar policy lines. Notable examples are The Universal Party, International Workingmen's Association (also called the First International), the Socialist International (also called the Second International), the Communist International (also called the Third International), and the Fourth International, as organizations of working class parties, or the Liberal International (yellow), Hizb ut-Tahrir, Christian Democratic International and the International Democrat Union (blue). Organized in Italy in 1945, the International Communist Party, since 1974 headquartered in Florence has sections in six countries.[citation needed] Worldwide green parties have recently established the Global Greens. The Universal Party, The Socialist International, the Liberal International, and the International Democrat Union are all based in London. Some administrations (e.g. Hong Kong) outlaw formal linkages between local and foreign political organizations, effectively outlawing international political parties.
When did political parties organize themselves into international organizations?
A:
19th and 20th century