Problem: Frédéric Chopin:

In September 1828 Chopin, while still a student, visited Berlin with a family friend, zoologist Feliks Jarocki, enjoying operas directed by Gaspare Spontini and attending concerts by Carl Friedrich Zelter, Felix Mendelssohn and other celebrities. On an 1829 return trip to Berlin, he was a guest of Prince Antoni Radziwiłł, governor of the Grand Duchy of Posen—himself an accomplished composer and aspiring cellist. For the prince and his pianist daughter Wanda, he composed his Introduction and Polonaise brillante in C major for cello and piano, Op. 3.

Who did Chopin go to Berlin with?
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A: Feliks Jarocki


Problem: The use of the term for the Iranian language family was introduced in 1836 by Christian Lassen. Robert Needham Cust used the term Irano-Aryan in 1878, and Orientalists such as George Abraham Grierson and Max Müller contrasted Irano-Aryan (Iranian) and Indo-Aryan (Indic). Some recent scholarship, primarily in German, has revived this convention.
What did George Abraham Grierson and Christian Lassen contrast?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
An important part of traditional, pre-generative schools of phonology is studying which sounds can be grouped into distinctive units within a language; these units are known as phonemes. For example, in English, the "p" sound in pot is aspirated (pronounced [pʰ]) while that in spot is not aspirated (pronounced [p]). However, English speakers intuitively treat both sounds as variations (allophones) of the same phonological category, that is of the phoneme /p/. (Traditionally, it would be argued that if an aspirated [pʰ] were interchanged with the unaspirated [p] in spot, native speakers of English would still hear the same words; that is, the two sounds are perceived as "the same" /p/.) In some other languages, however, these two sounds are perceived as different, and they are consequently assigned to different phonemes. For example, in Thai, Hindi, and Quechua, there are minimal pairs of words for which aspiration is the only contrasting feature (two words can have different meanings but with the only difference in pronunciation being that one has an aspirated sound where the other has an unaspirated one).
What is another word for phoneme?
A: unanswerable


Context and question: In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "flammable air". He speculated that "flammable air" was in fact identical to the hypothetical substance called "phlogiston" and further finding in 1781 that the gas produces water when burned. He is usually given credit for its discovery as an element. In 1783, Antoine Lavoisier gave the element the name hydrogen (from the Greek ὑδρο- hydro meaning "water" and -γενής genes meaning "creator") when he and Laplace reproduced Cavendish's finding that water is produced when hydrogen is burned.
What does gas produce when burned?
Answer: water


Question: The structure known as "Virgil's tomb" is found at the entrance of an ancient Roman tunnel (also known as "grotta vecchia") in Piedigrotta, a district two miles from the centre of Naples, near the Mergellina harbor, on the road heading north along the coast to Pozzuoli. While Virgil was already the object of literary admiration and veneration before his death, in the Middle Ages his name became associated with miraculous powers, and for a couple of centuries his tomb was the destination of pilgrimages and veneration.
Is there an answer to this question: Where did Virgil die?

Answer: unanswerable


QUES: The town's first significant defences were likely erected due to commercial interests, following the temporary seizure of St. John's by the Dutch admiral Michiel de Ruyter in June 1665. The inhabitants were able to fend off a second Dutch attack in 1673, when this time it was defended by Christopher Martin, an English merchant captain. Martin landed six cannons from his vessel, the Elias Andrews, and constructed an earthen breastwork and battery near chain Rock commanding the Narrows leading into the harbour. With only twenty-three men, the valiant Martin beat off an attack by three Dutch warships. The English government planned to expand these fortifications (Fort William) in around 1689, but actual construction didn't begin until after the French admiral Pierre Le Moyne d'Iberville captured and destroyed the town in the Avalon Peninsula Campaign (1696). When 1500 English reinforcements arrived in late 1697 they found nothing but rubble where the town and fortifications had stood.

What admiral seized St. Johns in the 16th century?
What is the answer?
ANS:
unanswerable