Problem: Bird:

Birds (Aves) are a group of endothermic vertebrates, characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. Birds live worldwide and range in size from the 5 cm (2 in) bee hummingbird to the 2.75 m (9 ft) ostrich. They rank as the class of tetrapods with the most living species, at approximately ten thousand, with more than half of these being passerines, sometimes known as perching birds or, less accurately, as songbirds.

What is the smallest bird?
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A: bee hummingbird

Problem: History of science:

There are many notable contributors to the field of Chinese science throughout the ages. One of the best examples would be Shen Kuo (10311095), a polymath scientist and statesman who was the first to describe the magnetic-needle compass used for navigation, discovered the concept of true north, improved the design of the astronomical gnomon, armillary sphere, sight tube, and clepsydra, and described the use of drydocks to repair boats. After observing the natural process of the inundation of silt and the find of marine fossils in the Taihang Mountains (hundreds of miles from the Pacific Ocean), Shen Kuo devised a theory of land formation, or geomorphology. He also adopted a theory of gradual climate change in regions over time, after observing petrified bamboo found underground at Yan'an, Shaanxi province. If not for Shen Kuo's writing, the architectural works of Yu Hao would be little known, along with the inventor of movable type printing, Bi Sheng (990-1051). Shen's contemporary Su Song (10201101) was also a brilliant polymath, an astronomer who created a celestial atlas of star maps, wrote a pharmaceutical treatise with related subjects of botany, zoology, mineralogy, and metallurgy, and had erected a large astronomical clocktower in Kaifeng city in 1088. To operate the crowning armillary sphere, his clocktower featured an escapement mechanism and the world's oldest known use of an endless power-transmitting chain drive.

When was Shen Kuo alive?
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A: 10311095

Problem: Germans:

By the Middle Ages, large numbers of Jews lived in the Holy Roman Empire and had assimilated into German culture, including many Jews who had previously assimilated into French culture and had spoken a mixed Judeo-French language. Upon assimilating into German culture, the Jewish German peoples incorporated major parts of the German language and elements of other European languages into a mixed language known as Yiddish. However tolerance and assimilation of Jews in German society suddenly ended during the Crusades with many Jews being forcefully expelled from Germany and Western Yiddish disappeared as a language in Germany over the centuries, with German Jewish people fully adopting the German language.

Who migrated to Germany during the Crusades?
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A: unanswerable

Problem: Royal Dutch Shell:

Shell was vertically integrated and is active in every area of the oil and gas industry, including exploration and production, refining, distribution and marketing, petrochemicals, power generation and trading. It has minor renewable energy activities in the form of biofuels and wind. It has operations in over 90 countries, produces around 3.1 million barrels of oil equivalent per day and has 44,000 service stations worldwide. Shell Oil Company, its subsidiary in the United States, is one of its largest businesses.

What is the name of Shell's subsidiary in the United States?
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A:
Shell Oil Company