Problem: Solar energy:

Commercial solar water heaters began appearing in the United States in the 1890s. These systems saw increasing use until the 1920s but were gradually replaced by cheaper and more reliable heating fuels. As with photovoltaics, solar water heating attracted renewed attention as a result of the oil crises in the 1970s but interest subsided in the 1980s due to falling petroleum prices. Development in the solar water heating sector progressed steadily throughout the 1990s and growth rates have averaged 20% per year since 1999. Although generally underestimated, solar water heating and cooling is by far the most widely deployed solar technology with an estimated capacity of 154 GW as of 2007.

What was the estimated capacity of solar water heating and cooling in 2007?
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A: 154 GW

Problem: 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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Answer: Solar distillation

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Legislative Assembly of the Federal District is formed, as it is the case in all legislatures in Mexico, by both single-seat and proportional seats, making it a system of parallel voting. The Federal District is divided into 40 electoral constituencies of similar population which elect one representative by first-past-the-post plurality (FPP), locally called "uninominal deputies". The Federal District as a whole constitutes a single constituency for the parallel election of 26 representatives by proportionality (PR) with open-party lists, locally called "plurinominal deputies".
What is the local government of Mexico City called?
A: The Legislative Assembly of the Federal District

Context and question: In the past, small batches of amorphous metals with high surface area configurations (ribbons, wires, films, etc.) have been produced through the implementation of extremely rapid rates of cooling. This was initially termed "splat cooling" by doctoral student W. Klement at Caltech, who showed that cooling rates on the order of millions of degrees per second is sufficient to impede the formation of crystals, and the metallic atoms become "locked into" a glassy state. Amorphous metal wires have been produced by sputtering molten metal onto a spinning metal disk. More recently a number of alloys have been produced in layers with thickness exceeding 1 millimeter. These are known as bulk metallic glasses (BMG). Liquidmetal Technologies sell a number of zirconium-based BMGs. Batches of amorphous steel have also been produced that demonstrate mechanical properties far exceeding those found in conventional steel alloys.
What type of metal makes better alloys than Caltech?
Answer: unanswerable

Question: The BBC also introduced Ceefax, the first teletext service, starting in 1974. This service allows BBC viewers to view textual information such as the latest news on their television. CEEFAX has not made a full transition to digital television, instead being replaced by the new interactive BBCi service.
Is there an answer to this question: Ceefex replaced what interactive service?

Answer: unanswerable

Question: During the period of Late Mahayana Buddhism, four major types of thought developed: Madhyamaka, Yogacara, Tathagatagarbha, and Buddhist Logic as the last and most recent. In India, the two main philosophical schools of the Mahayana were the Madhyamaka and the later Yogacara. According to Dan Lusthaus, Madhyamaka and Yogacara have a great deal in common, and the commonality stems from early Buddhism. There were no great Indian teachers associated with tathagatagarbha thought.
Is there an answer to this question: In India the two main philosophical schools of the Mahayana were Madhyamaka and what else?

Answer:
Yogacara