Problem: Copper:

The major applications of copper are in electrical wires (60%), roofing and plumbing (20%) and industrial machinery (15%). Copper is mostly used as a pure metal, but when a higher hardness is required it is combined with other elements to make an alloy (5% of total use) such as brass and bronze. A small part of copper supply is used in production of compounds for nutritional supplements and fungicides in agriculture. Machining of copper is possible, although it is usually necessary to use an alloy for intricate parts to get good machinability characteristics.

What property does combining copper with brass or bronze create?
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A: hardness

Problem: Chesapeake Energy Arena in downtown is the principal multipurpose arena in the city which hosts concerts, NHL exhibition games, and many of the city's pro sports teams. In 2008, the Oklahoma City Thunder became the major tenant. Located nearby in Bricktown, the Chickasaw Bricktown Ballpark is the home to the city's baseball team, the Dodgers. "The Brick", as it is locally known, is considered one of the finest minor league parks in the nation.[citation needed]
Which team became the main tenant of the arena in 2008?
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Answer: Oklahoma City Thunder

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Garze Tibetan Autonomous Prefecture and Ngawa Tibetan and Qiang Autonomous Prefecture in western Sichuan are populated by Tibetans and Qiang people. Tibetans speak the Khams and Amdo Tibetan, which are Tibetic languages, as well as various Qiangic languages. The Qiang speak Qiangic languages and often Tibetic languages as well. The Yi people of Liangshan Yi Autonomous Prefecture in southern Sichuan speak the Nuosu language, which is one of the Lolo-Burmese languages; Yi is written using the Yi script, a syllabary standardized in 1974. The Southwest University for Nationalities has one of China's most prominent Tibetology departments, and the Southwest Minorities Publishing House prints literature in minority languages. In the minority inhabited regions of Sichuan, there is bi-lingual signage and public school instruction in non-Mandarin minority languages.
What language do the Mandarin people speak?
A: unanswerable

Context and question: One way to divide hunter-gatherer groups is by their return systems. James Woodburn uses the categories "immediate return" hunter-gatherers for egalitarian and "delayed return" for nonegalitarian. Immediate return foragers consume their food within a day or two after they procure it. Delayed return foragers store the surplus food (Kelly, 31).
What does the immediate return system mean?
Answer: egalitarian

Question: Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. There are now three hydroelectricity plants larger than 10 GW: the Three Gorges Dam in China, Itaipu Dam across the Brazil/Paraguay border, and Guri Dam in Venezuela. The cost of hydroelectricity is low, making it a competitive source of renewable electricity. The average cost of electricity from a hydro plant larger than 10 megawatts is 3 to 5 U.S. cents per kilowatt-hour.
Is there an answer to this question: Hydropower is produced in how many countries?

Answer: 150

Question: The first game in Arena Football League history was played on June 19, 1987, between the Gladiators and Commandos at Pittsburgh Civic Arena in front of 12,117 fans. The game was deliberately not televised so that it could be analyzed and any follies and failures would not be subject to national public scrutiny. Following the inaugural game, tweaks and adjustments were made, and the first season continued. The Dynamite and Bruisers played in the first-ever televised AFL game the next night, on June 20, 1987, at the Rosemont Horizon in suburban Chicago on ESPN with Bob Rathbun and Lee Corso calling the play. The broadcast showed a short clip of the Commandos-Gladiators game. Each team played six games, two against each other team. The top two teams, Denver and Pittsburgh, then competed in the first-ever AFL championship game, ArenaBowl I.
Is there an answer to this question: At what venue did the first televised Arena Football League game occur?

Answer:
the Rosemont Horizon