The problem: Answer a question about this article:
Increasing state control over the oil sector, the RCC began a program of nationalization, starting with the expropriation of British Petroleum's share of the British Petroleum-N.B. Hunt Sahir Field in December 1971. In September 1973, it was announced that all foreign oil producers active in Libya were to be nationalized. For Gaddafi, this was an important step towards socialism. It proved an economic success; while gross domestic product had been $3.8 billion in 1969, it had risen to $13.7 billion in 1974, and $24.5 billion in 1979. In turn, the Libyans' standard of life greatly improved over the first decade of Gaddafi's administration, and by 1979 the average per-capita income was at $8,170, up from $40 in 1951; this was above the average of many industrialized countries like Italy and the U.K.
In 1979, how much did the average per capita income change for Libyans?
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The answer: by 1979 the average per-capita income was at $8,170, up from $40 in 1951

The problem: Answer a question about this article:
There is a strong relationship between the properties of wood and the properties of the particular tree that yielded it. The density of wood varies with species. The density of a wood correlates with its strength (mechanical properties). For example, mahogany is a medium-dense hardwood that is excellent for fine furniture crafting, whereas balsa is light, making it useful for model building. One of the densest woods is black ironwood.
What property of wood has a correlation to its density?
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The answer: strength

The problem: Answer a question about this article:
By design, it is difficult to insert a USB plug into its receptacle incorrectly. The USB specification states that the required USB icon must be embossed on the "topside" of the USB plug, which "...provides easy user recognition and facilitates alignment during the mating process." The specification also shows that the "recommended" "Manufacturer's logo" ("engraved" on the diagram but not specified in the text) is on the opposite side of the USB icon. The specification further states, "The USB Icon is also located adjacent to each receptacle. Receptacles should be oriented to allow the icon on the plug to be visible during the mating process." However, the specification does not consider the height of the device compared to the eye level height of the user, so the side of the cable that is "visible" when mated to a computer on a desk can depend on whether the user is standing or kneeling.
How is the USB icon located to each receptacle?
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The answer: adjacent

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Paris was in its artistic prime in the 19th century and early 20th century, when it had a colony of artists established in the city and in art schools associated with some of the finest painters of the times: Manet, Monet, Berthe Morisot, Gauguin, Renoir and others. The French Revolution and political and social change in France had a profound influence on art in the capital. Paris was central to the development of Romanticism in art, with painters such as Gericault. Impressionism, Art Nouveau, Symbolism, Fauvism Cubism and Art Deco movements all evolved in Paris. In the late 19th century, many artists in the French provinces and worldwide flocked to Paris to exhibit their works in the numerous salons and expositions and make a name for themselves. Artists such as Pablo Picasso, Henri Matisse, Vincent van Gogh, Paul Cezanne, Jean Metzinger, Albert Gleizes, Henri Rousseau, Marc Chagall, Amedeo Modigliani and many others became associated with Paris. Picasso, living in Montmartre, painted his famous La Famille de Saltimbanques and Les Demoiselles d'Avignon between 1905 and 1907. Montmartre and Montparnasse became centres for artistic production.
Between what two years did Picasso paint La Famille de Saltimbanques and Les Demoiselles d'Avignon?
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The answer:
1905 and 1907