[Q]: Extract the answer to the question from the following context. Question: What mineral involves cooper having though to be the cause of its color? Context: Many minerals provide pigments which have been used in green paints and dyes over the centuries. Pigments, in this case, are minerals which reflect the color green, rather that emitting it through luminescent or phosphorescent qualities. The large number of green pigments makes it impossible to mention them all. Among the more notable green minerals, however is the emerald, which is colored green by trace amounts of chromium and sometimes vanadium. Chromium(III) oxide (Cr2O3), is called chrome green, also called viridian or institutional green when used as a pigment. For many years, the source of amazonite's color was a mystery. Widely thought to have been due to copper because copper compounds often have blue and green colors, the blue-green color is likely to be derived from small quantities of lead and water in the feldspar. Copper is the source of the green color in malachite pigments, chemically known as basic copper(II) carbonate.
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[A]: amazonite

[Q]: Extract the answer to the question from the following context. Question: What was formed in 1850 to help with policing? Context: In the American Old West, policing was often of very poor quality.[citation needed] The Army often provided some policing alongside poorly resourced sheriffs and temporarily organized posses.[citation needed] Public organizations were supplemented by private contractors, notably the Pinkerton National Detective Agency, which was hired by individuals, businessmen, local governments and the federal government. At its height, the Pinkerton Agency's numbers exceeded those of the United States Army.[citation needed]
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[A]: Pinkerton National Detective Agency

[Q]: Extract the answer to the question from the following context. Question: What does the p in 720p stand for? Context: It also includes the alternative 14401152 HDMAC scan format. (According to some reports, a mooted 750-line (720p) format (720 progressively scanned lines) was viewed by some at the ITU as an enhanced television format rather than a true HDTV format, and so was not included, although 19201080i and 1280720p systems for a range of frame and field rates were defined by several US SMPTE standards.)
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[A]: progressively

[Q]: Extract the answer to the question from the following context. Question: WHat is second mentioned location? Context: Cork was one of the most rail-oriented cities in Ireland, featuring eight stations at various times. The main route, still much the same today, is from Dublin Heuston. Originally terminating on the city's outskirts at Blackpool, the route now reaches the city centre terminus of Kent Station via Glanmire tunnel. Now a through station, the line through Kent connects the towns of Cobh and Midleton east of the city. This also connected to the seaside town of Youghal, until the 1980s.[citation needed]
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[A]:
Ireland