Problem: The earliest known avialan fossils come from the Tiaojishan Formation of China, which has been dated to the late Jurassic period (Oxfordian stage), about 160 million years ago. The avialan species from this time period include Anchiornis huxleyi, Xiaotingia zhengi, and Aurornis xui. The well-known early avialan, Archaeopteryx, dates from slightly later Jurassic rocks (about 155 million years old) from Germany. Many of these early avialans shared unusual anatomical features that may be ancestral to modern birds, but were later lost during bird evolution. These features include enlarged claws on the second toe which may have been held clear of the ground in life, and long feathers or "hind wings" covering the hind limbs and feet, which may have been used in aerial maneuvering.
The Oxfordian stage is also known as what?
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Answer: late Jurassic period

Problem: In 2008, Bloomberg claimed child labour in copper and cobalt mines that supplied Chinese companies in Congo. The children are creuseurs, that is they dig the ore by hand, carry sacks of ores on their backs, and these are then purchased by these companies. Over 60 of Katanga's 75 processing plants are owned by Chinese companies and 90 percent of the region's minerals go to China. An African NGO report claimed 80,000 child labourers under the age of 15, or about 40% of all miners, were supplying ore to Chinese companies in this African region. Amnesty International alleged in 2016 that some cobalt sold by Congo Dongfang Mining was produced by child labor, and that it was being used in lithium-ion batteries powering electric cars and mobile devices worldwide.
What is the cobalt used for?
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Answer: lithium-ion batteries powering electric cars and mobile devices worldwide

Problem: In addition to the cathedral, Strasbourg houses several other medieval churches that have survived the many wars and destructions that have plagued the city: the Romanesque Eglise Saint-Etienne, partly destroyed in 1944 by Allied bombing raids, the part Romanesque, part Gothic, very large Eglise Saint-Thomas with its Silbermann organ on which Wolfgang Amadeus Mozart and Albert Schweitzer played, the Gothic Eglise protestante Saint-Pierre-le-Jeune with its crypt dating back to the seventh century and its cloister partly from the eleventh century, the Gothic Eglise Saint-Guillaume with its fine early-Renaissance stained glass and furniture, the Gothic Eglise Saint-Jean, the part Gothic, part Art Nouveau Eglise Sainte-Madeleine, etc. The Neo-Gothic church Saint-Pierre-le-Vieux Catholique (there is also an adjacent church Saint-Pierre-le-Vieux Protestant) serves as a shrine for several 15th-century wood worked and painted altars coming from other, now destroyed churches and installed there for public display. Among the numerous secular medieval buildings, the monumental Ancienne Douane (old custom-house) stands out.
What style of building is the Ancienne Douane?
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Answer:
unanswerable