Problem: Boston:

In 2010, Boston was estimated to have 617,594 residents (a density of 12,200 persons/sq mile, or 4,700/km2) living in 272,481 housing units— a 5% population increase over 2000. The city is the third most densely populated large U.S. city of over half a million residents. Some 1.2 million persons may be within Boston's boundaries during work hours, and as many as 2 million during special events. This fluctuation of people is caused by hundreds of thousands of suburban residents who travel to the city for work, education, health care, and special events.

What is the density of Boston's population?
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A: 12,200 persons/sq mile


Problem: Neptune also resembles Uranus in its magnetosphere, with a magnetic field strongly tilted relative to its rotational axis at 47° and offset at least 0.55 radii, or about 13500 km from the planet's physical centre. Before Voyager 2's arrival at Neptune, it was hypothesised that Uranus's tilted magnetosphere was the result of its sideways rotation. In comparing the magnetic fields of the two planets, scientists now think the extreme orientation may be characteristic of flows in the planets' interiors. This field may be generated by convective fluid motions in a thin spherical shell of electrically conducting liquids (probably a combination of ammonia, methane and water) resulting in a dynamo action.
 What fluids aren't in Neptune's interior?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The history of the Greek people is closely associated with the history of Greece, Cyprus, Constantinople, Asia Minor and the Black Sea. During the Ottoman rule of Greece, a number of Greek enclaves around the Mediterranean were cut off from the core, notably in Southern Italy, the Caucasus, Syria and Egypt. By the early 20th century, over half of the overall Greek-speaking population was settled in Asia Minor (now Turkey), while later that century a huge wave of migration to the United States, Australia, Canada and elsewhere created the modern Greek diaspora.
The anthology of the Greek world is intimately joined with what areas of the world ?
A: history of the Greek people is closely associated with the history of Greece, Cyprus, Constantinople, Asia Minor and the Black Sea.


Context and question: In mid-2004 Madonna embarked on the Re-Invention World Tour in the U.S., Canada, and Europe. It became the highest-grossing tour of 2004, earning around $120 million and became the subject of her documentary I'm Going to Tell You a Secret. In November 2004, she was inducted into the UK Music Hall of Fame as one of its five founding members, along with The Beatles, Elvis Presley, Bob Marley, and U2. In January 2005, Madonna performed a cover version of the John Lennon song "Imagine" at Tsunami Aid. She also performed at the Live 8 benefit concert in London in July 2005.
When did Madonna perform at the Live 8 benefit concert in the UK?
Answer: July 2005.


Question: From 2006, the growth of the city extended into "green wedges" and beyond the city's urban growth boundary. Predictions of the city's population reaching 5 million people pushed the state government to review the growth boundary in 2008 as part of its Melbourne @ Five Million strategy. In 2009, Melbourne was less affected by the Late-2000s financial crisis in comparison to other Australian cities. At this time, more new jobs were created in Melbourne than any other Australian city—almost as many as the next two fastest growing cities, Brisbane and Perth, combined, and Melbourne's property market remained strong, resulting in historically high property prices and widespread rent increases.
Is there an answer to this question: What is the name given to Melbourne's population strategy that was revised in 2008? 

Answer: Melbourne @ Five Million strategy


A strong and prominent a cappella tradition was begun in the midwest part of the United States in 1911 by F. Melius Christiansen, a music faculty member at St. Olaf College in Northfield, Minnesota. The St. Olaf College Choir was established as an outgrowth of the local St. John's Lutheran Church, where Christiansen was organist and the choir was composed, at least partially, of students from the nearby St. Olaf campus. The success of the ensemble was emulated by other regional conductors, and a rich tradition of a cappella choral music was born in the region at colleges like Concordia College (Moorhead, Minnesota), Augustana College (Rock Island, Illinois), Wartburg College (Waverly, Iowa), Luther College (Decorah, Iowa), Gustavus Adolphus College (St. Peter, Minnesota), Augustana College (Sioux Falls, South Dakota), and Augsburg College (Minneapolis, Minnesota). The choirs typically range from 40 to 80 singers and are recognized for their efforts to perfect blend, intonation, phrasing and pitch in a large choral setting.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What do a capella choirs struggle to perfect in a large choral setting?
Ah, so..
unanswerable