Problem: Russian language:

According to the Institute of Russian Language of the Russian Academy of Sciences, an optional acute accent ( ) may, and sometimes should, be used to mark stress. For example, it is used to distinguish between otherwise identical words, especially when context does not make it obvious: / (lock/castle), / (worthwhile/standing), / (this is odd/this is marvelous), / (attaboy/fine young man), / (I shall learn it/I recognize it), / (to be cutting/to have cut); to indicate the proper pronunciation of uncommon words, especially personal and family names (, , , , ), and to show which is the stressed word in a sentence ( ?/ ?/ ? Was it you who ate the cookie?/Did you eat the cookie?/Was it the cookie that you ate?). Stress marks are mandatory in lexical dictionaries and books for children or Russian learners.

Where is context mandatory for children and Russian learners?
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A: unanswerable

Problem: The team worked on a Wii control scheme, adapting camera control and the fighting mechanics to the new interface. A prototype was created that used a swinging gesture to control the sword from a first-person viewpoint, but was unable to show the variety of Link's movements. When the third-person view was restored, Aonuma thought it felt strange to swing the Wii Remote with the right hand to control the sword in Link's left hand, so the entire Wii version map was mirrored.[p] Details about Wii controls began to surface in December 2005 when British publication NGC Magazine claimed that when a GameCube copy of Twilight Princess was played on the Revolution, it would give the player the option of using the Revolution controller. Miyamoto confirmed the Revolution controller-functionality in an interview with Nintendo of Europe and Time reported this soon after. However, support for the Wii controller did not make it into the GameCube release. At E3 2006, Nintendo announced that both versions would be available at the Wii launch, and had a playable version of Twilight Princess for the Wii.[p] Later, the GameCube release was pushed back to a month after the launch of the Wii.
What ended up not being supported in the Wii version of Twilight Princess?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The Quran and Muhammad talked about racial equality and justice as in The Farewell Sermon. Tribal and nationalistic differences were discouraged. But after Muhammad's passing, the old tribal differences between the Arabs started to resurface. Following the RomanPersian Wars and the ByzantineSassanid Wars, deep rooted differences between Iraq, formally under the Persian Sassanid Empire, and Syria, formally under the Byzantine Empire, also existed. Each wanted the capital of the newly established Islamic State to be in their area. Previously, the second caliph Umar was very firm on the governors and his spies kept an eye on them. If he felt that a governor or a commander was becoming attracted to wealth, he had him removed from his position.
Who controlled Iraq before the Arabs?
A: Persian Sassanid Empire

Context and question: A fleet carrier is intended to operate with the main fleet and usually provides an offensive capability. These are the largest carriers capable of fast speeds. By comparison, escort carriers were developed to provide defense for convoys of ships. They were smaller and slower with lower numbers of aircraft carried. Most were built from mercantile hulls or, in the case of merchant aircraft carriers, were bulk cargo ships with a flight deck added on top. Light aircraft carriers were carriers that were fast enough to operate with the fleet but of smaller size with reduced aircraft capacity. Soviet aircraft carriers now in use by Russia are actually called heavy aviation cruisers, these ships while sized in the range of large fleet carriers were designed to deploy alone or with escorts and provide both strong defensive weaponry and heavy offensive missiles equivalent to a guided missile cruiser in addition to supporting fighters and helicopters.
What purpose were excort carriers developed for?
Answer: to provide defense for convoys of ships

Question: Selfridges was established in 1909 by American-born Harry Gordon Selfridge on Oxford Street. The company's innovative marketing promoted the radical notion of shopping for pleasure rather than necessity and its techniques were adopted by modern department stores the world over. The store was extensively promoted through paid advertising. The shop floors were structured so that goods could be made more accessible to customers. There were elegant restaurants with modest prices, a library, reading and writing rooms, special reception rooms for French, German, American and "Colonial" customers, a First Aid Room, and a Silence Room, with soft lights, deep chairs, and double-glazing, all intended to keep customers in the store as long as possible. Staff members were taught to be on hand to assist customers, but not too aggressively, and to sell the merchandise. Selfridge attracted shoppers with educational and scientific exhibits; in 1909, Louis Bleriot's monoplane was exhibited at Selfridges (Bleriot was the first to fly over the English Channel), and the first public demonstration of television by John Logie Baird took place in the department store in 1925.
Is there an answer to this question: What sort of customers did Selfridges most often cater to?

Answer: shoppers with educational and scientific exhibits

Problem: Estonian language:

Estonian (eesti keel [esti kel] ( listen)) is the official language of Estonia, spoken natively by about 1.1 million people in Estonia and tens of thousands in various migrant communities. It belongs to the Finnic branch of the Uralic language family.

What country has Estonian as its official language?
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A:
Estonian