Problem: Solar energy:

Solar distillation can be used to make saline or brackish water potable. The first recorded instance of this was by 16th-century Arab alchemists. A large-scale solar distillation project was first constructed in 1872 in the Chilean mining town of Las Salinas. The plant, which had solar collection area of 4,700 m2 (51,000 sq ft), could produce up to 22,700 L (5,000 imp gal; 6,000 US gal) per day and operate for 40 years. Individual still designs include single-slope, double-slope (or greenhouse type), vertical, conical, inverted absorber, multi-wick, and multiple effect. These stills can operate in passive, active, or hybrid modes. Double-slope stills are the most economical for decentralized domestic purposes, while active multiple effect units are more suitable for large-scale applications.

What is used to make saline or brackish water drinkable?
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A: Solar distillation


Problem: However, if the debt rescheduling causes losses on loans held by European banks, it weakens the private banking system, which then puts pressure on the central bank to come to the aid of those banks. Private-sector bond holders are an integral part of the public and private banking system. Another possible response is for wealthy member countries to guarantee or purchase the debt of countries that have defaulted or are likely to default. This alternative requires that the tax revenues and credit of the wealthy member countries be used to refinance the previous borrowing of the weaker member countries, and is politically controversial.
What is never to be used to guarantee the debtors repayment, by the banks assuming their debt?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
As the capital of Uruguay, Montevideo is home to a number of festivals and carnivals including a Gaucho festival when people ride through the streets on horseback in traditional gaucho gear. The major annual festival is the annual Montevideo Carnaval which is part of the national festival of Carnival Week, celebrated throughout Uruguay, with central activities in the capital, Montevideo. Officially, the public holiday lasts for two days on Carnival Monday and Shrove Tuesday preceding Ash Wednesday, but due to the prominence of the festival, most shops and businesses close for the entire week. During carnival there are many open-air stage performances and competitions and the streets and houses are vibrantly decorated. "Tablados" or popular scenes, both fixed and movable, are erected in the whole city. Notable displays include "Desfile de las Llamadas" ("Parade of the Calls"), which is a grand united parade held on the south part of downtown, where it used to be a common ritual back in the early 20th century. Due to the scale of the festival, preparation begins as early as December with an election of the "zonal beauty queens" to appear in the carnival.
What is the major annual festival in Montevideo?
A: the annual Montevideo Carnaval


Context and question: The theory that race is merely a social construct has been challenged by the findings of researchers at the Stanford University School of Medicine, published in the American Journal of Human Genetics as "Genetic Structure, Self-Identified Race/Ethnicity, and Confounding in Case-Control Association Studies". One of the researchers, Neil Risch, noted: "we looked at the correlation between genetic structure [based on microsatellite markers] versus self-description, we found 99.9% concordance between the two. We actually had a higher discordance rate between self-reported sex and markers on the X chromosome! So you could argue that sex is also a problematic category. And there are differences between sex and gender; self-identification may not be correlated with biology perfectly. And there is sexism."
What is a problematic category in addition to race?
Answer: sex


Question: The club's success in the late 1990s and first decade of the 21st century owed a great deal to the 1996 appointment of Arsène Wenger as manager. Wenger brought new tactics, a new training regime and several foreign players who complemented the existing English talent. Arsenal won a second League and Cup double in 1997–98 and a third in 2001–02. In addition, the club reached the final of the 1999–2000 UEFA Cup (losing on penalties to Galatasaray), were victorious in the 2003 and 2005 FA Cups, and won the Premier League in 2003–04 without losing a single match, an achievement which earned the side the nickname "The Invincibles". The feat came within a run of 49 league matches unbeaten from 7 May 2003 to 24 October 2004, a national record.
Is there an answer to this question: In what season did Arsenal win their second League and Cup double?

Answer: 1997–98


Question: Parallel to the military developments emerged also a constantly more elaborate chivalric code of conduct for the warrior class. This new-found ethos can be seen as a response to the diminishing military role of the aristocracy, and gradually it became almost entirely detached from its military origin. The spirit of chivalry was given expression through the new (secular) type of chivalric orders; the first of these was the Order of St. George, founded by Charles I of Hungary in 1325, while the best known was probably the English Order of the Garter, founded by Edward III in 1348.
Is there an answer to this question: In what year was the Order of the Garter established?

Answer:
1348