Problem: Color in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II) oxide (FeO) impurities of up to 0.1 wt% produce a green tint, which can be viewed in thick pieces or with the aid of scientific instruments. Further FeO and Cr2O3 additions may be used for the production of green bottles. Sulfur, together with carbon and iron salts, is used to form iron polysulfides and produce amber glass ranging from yellowish to almost black. A glass melt can also acquire an amber color from a reducing combustion atmosphere. Manganese dioxide can be added in small amounts to remove the green tint given by iron(II) oxide. When used in art glass or studio glass is colored using closely guarded recipes that involve specific combinations of metal oxides, melting temperatures and 'cook' times. Most colored glass used in the art market is manufactured in volume by vendors who serve this market although there are some glassmakers with the ability to make their own color from raw materials.
What other than additives can give glass a yellow color?
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Answer: reducing combustion atmosphere

Problem: It is also known as the Wenchuan earthquake (Chinese: ; pinyin: Wenchuan da dizhen; literally: "Great Wenchuan earthquake"), after the location of the earthquake's epicenter, Wenchuan County, Sichuan. The epicenter was 80 kilometres (50 mi) west-northwest of Chengdu, the provincial capital, with a focal depth of 19 km (12 mi). The earthquake was also felt in nearby countries and as far away as both Beijing and Shanghai1,500 km (930 mi) and 1,700 km (1,060 mi) awaywhere office buildings swayed with the tremor. Strong aftershocks, some exceeding magnitude 6, continued to hit the area even months after the main quake, causing new casualties and damage.
What was the focal depth of the earthquake?
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Answer: 19 km

Problem: Napoleon Bonaparte (/npolin, -poljn/; French: [naple bnapat], born Napoleone di Buonaparte; 15 August 1769 5 May 1821) was a French military and political leader who rose to prominence during the French Revolution and led several successful campaigns during the Revolutionary Wars. As Napoleon I, he was Emperor of the French from 1804 until 1814, and again in 1815. Napoleon dominated European and global affairs for more than a decade while leading France against a series of coalitions in the Napoleonic Wars. He won most of these wars and the vast majority of his battles, building a large empire that ruled over continental Europe before its final collapse in 1815. Often considered one of the greatest commanders in history, his wars and campaigns are studied at military schools worldwide. He also remains one of the most celebrated and controversial political figures in Western history. In civil affairs, Napoleon had a major long-term impact by bringing liberal reforms to the territories that he conquered, especially the Low Countries, Switzerland, and large parts of modern Italy and Germany. He implemented fundamental liberal policies in France and throughout Western Europe.[note 1] His lasting legal achievement, the Napoleonic Code, has been adopted in various forms by a quarter of the world's legal systems, from Japan to Quebec.
During what historical event did Napoleon rise to prominence?
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Answer:
the French Revolution