Problem: Bermuda:

The war had removed Bermuda's primary trading partners, the American colonies, from the empire, and dealt a harsh blow to Bermuda's merchant shipping trade. This also suffered due to the deforestation of Bermuda, as well as the advent of metal ships and steam propulsion, for which it did not have raw materials. During the course of the following War of 1812, the primary market for Bermuda's salt disappeared as the Americans developed their own sources. Control of the Turks had passed to the Bahamas in 1819.

Who did control of the Bahamas pass to in 1819?
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A: unanswerable


Problem: The early 1990s marked the softening of urban R&B at the same time alternative rock emerged and traditional pop saw a significant resurgence. This in part led to a widening of the market, not only allowing to cater to more niche markets, but it also became customary for artists to make AC-friendly singles.
What happened to urban R&B in the early 1990s?
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Answer: softening


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Current manager, Roberto Martínez, is the fourteenth permanent holder of the position since it was established in 1939. There have also been four caretaker managers, and before 1939 the team was selected by either the club secretary or by committee. The club's longest-serving manager has been Harry Catterick, who was in charge of the team from 1961–73, taking in 594 first team matches. The Everton manager to win most domestic and international trophies is Howard Kendall, who won two Division One championships, the 1984 FA Cup, the 1984 UEFA Cup Winners' Cup, and three Charity Shields.
In what year did Everton have its first caretaker manager?
A: unanswerable


Context and question: All birds lay amniotic eggs with hard shells made mostly of calcium carbonate. Hole and burrow nesting species tend to lay white or pale eggs, while open nesters lay camouflaged eggs. There are many exceptions to this pattern, however; the ground-nesting nightjars have pale eggs, and camouflage is instead provided by their plumage. Species that are victims of brood parasites have varying egg colours to improve the chances of spotting a parasite's egg, which forces female parasites to match their eggs to those of their hosts.
All birds lay eggs with hard shells made mostly out of what?
Answer: calcium carbonate


Question: As the premiers did not come to an agreement on this question, the Parliamentary Council was supposed to address this issue. Its provisions are reflected in Article 29. There was a binding provision for a new delimitation of the federal territory: the Federal Territory must be revised ... (paragraph 1). Moreover, in territories or parts of territories whose affiliation with a Land had changed after 8 May 1945 without a referendum, people were allowed to petition for a revision of the current status within a year after the promulgation of the Basic Law (paragraph 2). If at least one tenth of those entitled to vote in Bundestag elections were in favour of a revision, the federal government had to include the proposal into its legislation. Then a referendum was required in each territory or part of a territory whose affiliation was to be changed (paragraph 3). The proposal should not take effect if within any of the affected territories a majority rejected the change. In this case, the bill had to be introduced again and after passing had to be confirmed by referendum in the Federal Republic as a whole (paragraph 4). The reorganization should be completed within three years after the Basic Law had come into force (paragraph 6).
Is there an answer to this question: What fraction of people voted in Bundestag elections?

Answer: unanswerable


Question: The University of Michigan shapes Ann Arbor's economy significantly. It employs about 30,000 workers, including about 12,000 in the medical center. Other employers are drawn to the area by the university's research and development money, and by its graduates. High tech, health services and biotechnology are other major components of the city's economy; numerous medical offices, laboratories, and associated companies are located in the city. Automobile manufacturers, such as General Motors and Visteon, also employ residents.
Is there an answer to this question: What is the employee count of the University of Michigan?

Answer:
30,000