The problem: Answer a question about this article:
Child labour played an important role in the Industrial Revolution from its outset, often brought about by economic hardship. The children of the poor were expected to contribute to their family income. In 19th-century Great Britain, one-third of poor families were without a breadwinner, as a result of death or abandonment, obliging many children to work from a young age. In England and Scotland in 1788, two-thirds of the workers in 143 water-powered cotton mills were described as children. A high number of children also worked as prostitutes. The author Charles Dickens worked at the age of 12 in a blacking factory, with his family in debtor's prison.
Where was Charles Dickens employed as a child?
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The answer: blacking factory


The problem: Answer a question about this article:
The axiom of foundation established that every set can be constructed from the bottom up in an ordered succession of steps by way of the principles of Zermelo and Fraenkel, in such a manner that if one set belongs to another then the first must necessarily come before the second in the succession, hence excluding the possibility of a set belonging to itself. To demonstrate that the addition of this new axiom to the others did not produce contradictions, von Neumann introduced a method of demonstration, called the method of inner models, which later became an essential instrument in set theory.
Zermelo and Fraenkel's axiom of foundation established that every set be constructed how?
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The answer: from the bottom up in an ordered succession of steps


The problem: Answer a question about this article:
Mercury has been smelted from cinnabar for thousands of years. Mercury dissolves many metals, such as gold, silver, and tin, to form amalgams (an alloy in a soft paste, or liquid form at ambient temperature). Amalgams have been used since 200 BC in China for plating objects with precious metals, called gilding, such as armor and mirrors. The ancient Romans often used mercury-tin amalgams for gilding their armor. The amalgam was applied as a paste and then heated until the mercury vaporized, leaving the gold, silver, or tin behind. Mercury was often used in mining, to extract precious metals like gold and silver from their ores.
Since when have Amalgams been used?
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The answer: 200 BC


The problem: Answer a question about this article:
Qin armies finished their conquest of the kingdoms of Shu and Ba by 316 BC. Any written records and civil achievements of earlier kingdoms were destroyed. Qin administrators introduced improved agricultural technology. Li Bing, engineered the Dujiangyan irrigation system to control the Min River, a major tributary of the Yangtze. This innovative hydraulic system was composed of movable weirs which could be adjusted for high or low water flow according to the season, to either provide irrigation or prevent floods. The increased agricultural output and taxes made the area a source of provisions and men for Qin's unification of China.
The Min River is a major tributary of what river? 
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The answer:
Yangtze