Problem: Biodiversity:

The history of biodiversity during the Phanerozoic (the last 540 million years), starts with rapid growth during the Cambrian explosion—a period during which nearly every phylum of multicellular organisms first appeared. Over the next 400 million years or so, invertebrate diversity showed little overall trend, and vertebrate diversity shows an overall exponential trend. This dramatic rise in diversity was marked by periodic, massive losses of diversity classified as mass extinction events. A significant loss occurred when rainforests collapsed in the carboniferous. The worst was the Permian-Triassic extinction event, 251 million years ago. Vertebrates took 30 million years to recover from this event.

What type of diversity showed an overall extinction trend?
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A: unanswerable


Problem: All the major British cities had flourishing department stores by the mid-or late nineteenth century. Increasingly, women became the major shoppers and middle-class households. Kendals (formerly Kendal Milne & Faulkner) in Manchester lays claim to being one of the first department stores and is still known to many of its customers as Kendal's, despite its 2005 name change to House of Fraser. The Manchester institution dates back to 1836 but had been trading as Watts Bazaar since 1796. At its zenith the store had buildings on both sides of Deansgate linked by a subterranean passage "Kendals Arcade" and an art nouveau tiled food hall. The store was especially known for its emphasis on quality and style over low prices giving it the nickname "the Harrods of the North", although this was due in part to Harrods acquiring the store in 1919. Other large Manchester stores included Paulden's (currently Debenhams) and Lewis's (now a Primark).
What business in Manchester claims to be the first department store? 
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Answer: Kendals (formerly Kendal Milne & Faulkner)


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Labour improved its performance in 1987, gaining 20 seats and so reducing the Conservative majority from 143 to 102. They were now firmly re-established as the second political party in Britain as the Alliance had once again failed to make a breakthrough with seats. A merger of the SDP and Liberals formed the Liberal Democrats. Following the 1987 election, the National Executive Committee resumed disciplinary action against members of Militant, who remained in the party, leading to further expulsions of their activists and the two MPs who supported the group.
What party lost 20 seats in 1987?
A: unanswerable


Context and question: Much of the early colonial art stemmed from the codices (Aztec illustrated books), aiming to recover and preserve some Aztec and other Amerindian iconography and history. From then, artistic expressions in Mexico were mostly religious in theme. The Metropolitan Cathedral still displays works by Juan de Rojas, Juan Correa and an oil painting whose authorship has been attributed to Murillo. Secular works of art of this period include the equestrian sculpture of Charles IV of Spain, locally known as El Caballito ("The little horse"). This piece, in bronze, was the work of Manuel Tolsá and it has been placed at the Plaza Tolsá, in front of the Palacio de Minería (Mining Palace). Directly in front of this building is the beautiful Museo Nacional de Arte (Munal) (the National Museum of Art).
Whose art is displayed at the large cathedral in Mexico City?
Answer: Juan de Rojas


Question: BBC Television returned on 7 June 1946 at 15:00. Jasmine Bligh, one of the original announcers, made the first announcement, saying, 'Good afternoon everybody. How are you? Do you remember me, Jasmine Bligh?'. The Mickey Mouse cartoon of 1939 was repeated twenty minutes later.[unreliable source?] Alexandra Palace was the home base of the channel until the early 1950s when the majority of production moved into the newly acquired Lime Grove Studios.[original research?]
Is there an answer to this question: Who was Alexandra Bligh?

Answer: unanswerable


After several failed attempts, in 1930 the first aeroplane reached Bermuda. A Stinson Detroiter seaplane flying from New York, it had to land twice in the ocean: once because of darkness and again to refuel. Navigation and weather forecasting improved in 1933 when the Royal Air Force (then responsible for providing equipment and personnel for the Royal Navy's Fleet Air Arm) established a station at the Royal Naval Dockyard to repair (and supply replacement) float planes for the fleet. In 1936 Luft Hansa began to experiment with seaplane flights from Berlin via the Azores with continuation to New York City.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What is Detroiter Stinson a type of?
Ah, so..
unanswerable