Problem: Estonia:

The capital of Danish Estonia (Danish: Hertugdmmet Estland) was Reval (Tallinn), founded at the place of Lyndanisse after the invasion of 1219. The Danes built the fortress of Castrum Danorum at Toompea Hill. Estonians still call their capital "Tallinn", which according to legend derives from Taani linna (meaning Danish town or castle). Reval was granted Lubeck city rights (1248) and joined the Hanseatic League. Even today, Danish influence can be seen in heraldic symbols. The Danish cross is on the city of Tallinn's coat of arms, and Estonia's coat of arms displays three lions similar to those found on the Danish coat of arms.

What was the capital of Danish Estonia?
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A: Reval

Problem: The doctrine of the last day and eschatology (the final fate of the universe) may be reckoned as the second great doctrine of the Quran. It is estimated that approximately one-third of the Quran is eschatological, dealing with the afterlife in the next world and with the day of judgment at the end of time. There is a reference to the afterlife on most pages of the Quran and belief in the afterlife is often referred to in conjunction with belief in God as in the common expression: "Believe in God and the last day". A number of suras such as 44, 56, 75, 78, 81 and 101 are directly related to the afterlife and its preparations. Some suras indicate the closeness of the event and warn people to be prepared for the imminent day. For instance, the first verses of Sura 22, which deal with the mighty earthquake and the situations of people on that day, represent this style of divine address: "O People! Be respectful to your Lord. The earthquake of the Hour is a mighty thing."
Which natural disaster features in Sura 22?
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Answer: earthquake

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The English term comics is used as a singular noun when it refers to the medium and a plural when referring to particular instances, such as individual strips or comic books. Though the term derives from the humorous (or comic) work that predominated in early American newspaper comic strips, it has become standard also for non-humorous works. It is common in English to refer to the comics of different cultures by the terms used in their original languages, such as manga for Japanese comics, or bandes dessinees for French-language comics. There is no consensus amongst theorists and historians on a definition of comics; some emphasize the combination of images and text, some sequentiality or other image relations, and others historical aspects such as mass reproduction or the use of recurring characters. The increasing cross-pollination of concepts from different comics cultures and eras has further made definition difficult.
When is the term comics considered singular rather than plural?
A: when it refers to the medium

Context and question: Above the forestry, there is often a band of short pine trees (Pinus mugo), which is in turn superseded by Alpenrosen, dwarf shrubs, typically Rhododendron ferrugineum (on acid soils) or Rhododendron hirsutum (on alkaline soils). Although the Alpenrose prefers acidic soil, the plants are found throughout the region. Above the tree line is the area defined as "alpine" where in the alpine meadow plants are found that have adapted well to harsh conditions of cold temperatures, aridity, and high altitudes. The alpine area fluctuates greatly because of regional fluctuations in tree lines.
Why does the alpine area fluctuate greatly?
Answer: because of regional fluctuations in tree lines.

Question: The difference in the above factors for the case of =0 is the reason that most broadcasting (transmissions intended for the public) uses vertical polarization. For receivers near the ground, horizontally polarized transmissions suffer cancellation. For best reception the receiving antennas for these signals are likewise vertically polarized. In some applications where the receiving antenna must work in any position, as in mobile phones, the base station antennas use mixed polarization, such as linear polarization at an angle (with both vertical and horizontal components) or circular polarization.
Is there an answer to this question: What is one use that would require an antenna to receive signals in various ways at once?

Answer: mobile phones

Problem: Tuvalu:

Reverse osmosis (R/O) desalination units supplement rainwater harvesting on Funafuti. The 65 m3 desalination plant operates at a real production level of around 40 m3 per day. R/O water is only intended to be produced when storage falls below 30%, however demand to replenish household storage supplies with tanker-delivered water means that the R/O desalination units are continually operating. Water is delivered at a cost of A$3.50 per m3. Cost of production and delivery has been estimated at A$6 per m3, with the difference subsidised by the government.

What type of desalination is used on Funafuti?
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A:
Reverse osmosis