Problem: Ann Arbor, Michigan:

Since the university's establishment in the city in 1837, the histories of the University of Michigan and Ann Arbor have been closely linked. The town became a regional transportation hub in 1839 with the arrival of the Michigan Central Railroad, and a north—south railway connecting Ann Arbor to Toledo and other markets to the south was established in 1878. Throughout the 1840s and the 1850s settlers continued to come to Ann Arbor. While the earlier settlers were primarily of British ancestry, the newer settlers also consisted of Germans, Irish, and African-Americans. In 1851, Ann Arbor was chartered as a city, though the city showed a drop in population during the Depression of 1873. It was not until the early 1880s that Ann Arbor again saw robust growth, with new immigrants coming from Greece, Italy, Russia, and Poland. Ann Arbor saw increased growth in manufacturing, particularly in milling. Ann Arbor's Jewish community also grew after the turn of the 20th century, and its first and oldest synagogue, Beth Israel Congregation, was established in 1916.

What railroad arrived in 1893?
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A: unanswerable


Problem: For instance, a common use of a database system is to track information about users, their name, login information, various addresses and phone numbers. In the navigational approach all of this data would be placed in a single record, and unused items would simply not be placed in the database. In the relational approach, the data would be normalized into a user table, an address table and a phone number table (for instance). Records would be created in these optional tables only if the address or phone numbers were actually provided.
What happens to full data fields in a navigational system?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
On November 4, 1979, a group of students seized the United States Embassy and took the embassy with 52 personnel and citizens hostage, after the United States refused to return Mohammad Reza Pahlavi to Iran to face trial in the court of the new regime. Attempts by the Jimmy Carter administration to negotiate for the release of the hostages, and a failed rescue attempt, helped force Carter out of office and brought Ronald Reagan to power. On Jimmy Carter's final day in office, the last hostages were finally set free as a result of the Algiers Accords.
Who seized the US Embassy in Iran in 1979?
A: a group of students


Context and question: The Boston Globe and the Boston Herald are two of the city's major daily newspapers. The city is also served by other publications such as Boston magazine, The Improper Bostonian, DigBoston, and the Boston edition of Metro. The Christian Science Monitor, headquartered in Boston, was formerly a worldwide daily newspaper but ended publication of daily print editions in 2009, switching to continuous online and weekly magazine format publications. The Boston Globe also releases a teen publication to the city's public high schools, called Teens in Print or T.i.P., which is written by the city's teens and delivered quarterly within the school year.
How often does The Christian Science monitor publish their magazine?
Answer: weekly


Question: From 1525 to 1917 14,503 titles were published in Estonian, as opposed to the 23,868 titles which were published between 1918 and 1940.[citation needed]
Is there an answer to this question: How many books were published in Etonian before 1525?

Answer: unanswerable


Question: According to Der Spiegel, credits given to European governments were disguised as "swaps" and consequently did not get registered as debt because Eurostat at the time ignored statistics involving financial derivatives. A German derivatives dealer had commented to Der Spiegel that "The Maastricht rules can be circumvented quite legally through swaps," and "In previous years, Italy used a similar trick to mask its true debt with the help of a different US bank." These conditions had enabled Greek as well as many other European governments to spend beyond their means, while meeting the deficit targets of the European Union and the monetary union guidelines. In May 2010, the Greek government deficit was again revised and estimated to be 13.6% which was the second highest in the world relative to GDP with Iceland in first place at 15.7% and Great Britain third with 12.6%. Public debt was forecast, according to some estimates, to hit 120% of GDP during 2010.
Is there an answer to this question: What was Greece's public debt forecast to hit as low of a percentage of GDP of in 2000?

Answer:
unanswerable