Problem: Catalan language:

Catalan verbs are traditionally divided into three conjugations, with vowel themes -a-, -e-, -i-, the last two being split into two subtypes. However, this division is mostly theoretical. Only the first conjugation is nowadays productive (with about 3500 common verbs), whereas the third (the subtype of servir, with about 700 common verbs) is semiproductive. The verbs of the second conjugation are fewer than 100, and it is not possible to create new ones, except by compounding.

Which conjugation has less than 100 verbs?
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A: second

Problem: St. John's was the starting point for the first non-stop transatlantic aircraft flight, by Alcock and Brown in a modified Vickers Vimy IV bomber, in June 1919, departing from Lester's Field in St. John's and ending in a bog near Clifden, Connemara, Ireland. In July 2005, the flight was duplicated by American aviator and adventurer Steve Fossett in a replica Vickers Vimy aircraft, with St. John's International Airport substituting for Lester's Field (now an urban and residential part of the city).
What aircraft did Steve Fossett use for his flight in July 2005?
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Answer: replica Vickers Vimy

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Most sports and physical activities are practiced wearing special clothing, for practical, comfort or safety reasons. Common sportswear garments include shorts, T-shirts, tennis shirts, leotards, tracksuits, and trainers. Specialized garments include wet suits (for swimming, diving or surfing), salopettes (for skiing) and leotards (for gymnastics). Also, spandex materials are often used as base layers to soak up sweat. Spandex is also preferable for active sports that require form fitting garments, such as volleyball, wrestling, track & field, dance, gymnastics and swimming.
What's an example of a form fitting garment?
A: Spandex

Context and question: There is a close connection between machine learning and compression: a system that predicts the posterior probabilities of a sequence given its entire history can be used for optimal data compression (by using arithmetic coding on the output distribution) while an optimal compressor can be used for prediction (by finding the symbol that compresses best, given the previous history). This equivalence has been used as a justification for using data compression as a benchmark for "general intelligence."
What has been used as a benchmark for "general intelligence"?
Answer: data compression

Question: The characteristic forms that were to define Gothic architecture grew out of Romanesque architecture and developed at several different geographic locations, as the result of different influences and structural requirements. While barrel vaults and groin vaults are typical of Romanesque architecture, ribbed vaults were used in the naves of two Romanesque churches in Caen, Abbey of Saint-Etienne and Abbaye aux Dames in 1120. Another early example is the nave and apse area of the Cathedral of Cefalu in 1131. The ribbed vault over the north transept at Durham Cathedral in England, built from 1128 to 1133, is probably earlier still and was the first time pointed arches were used in a high vault.
Is there an answer to this question: What type of vaults were lost in the Abbey of Saint-Etienne and Abbaye aux Dames?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Like most other regions of central and southern Germany, Thuringia has a significant industrial sector reaching back to the mid-19th-century industrialisation. The economic transition after the German reunification in 1990 led to the closure of most large-scale factories and companies, leaving small and medium-sized ones to dominate the manufacturing sector. Well-known industrial centres are Jena (a world centre for optical instruments with companies like Carl Zeiss, Schott and Jenoptik) and Eisenach, where BMW started its car production in the 1920s and an Opel factory is based today. The most important industrial branches today are engineering and metalworking, vehicle production and food industries. Especially the small and mid-sized towns in central and southwestern Thuringia (e.g. Arnstadt, Schmalkalden and Ohrdruf) are highly industrialised, whereas there are fewer industrial companies in the northern and eastern parts of the Land. Traditional industries like production of glass, porcelain and toys collapsed during the economic crises between 1930 and 1990.
When did modern industries like glass and robot making collapse?
A:
unanswerable