Problem: A cappella:

It is not clear exactly where collegiate a cappella began. The Rensselyrics of Rensselaer Polytechnic Institute (formerly known as the RPI Glee Club), established in 1873 is perhaps the oldest known collegiate a cappella group.[citation needed] However the longest continuously-singing group is probably The Whiffenpoofs of Yale University, which was formed in 1909 and once included Cole Porter as a member. Collegiate a cappella groups grew throughout the 20th century. Some notable historical groups formed along the way include Princeton University's Tigertones (1946), Colgate University's The Colgate 13 (1942), Dartmouth College's Aires (1946), Cornell University's Cayuga's Waiters (1949) and The Hangovers (1968), the University of Maine Maine Steiners (1958), the Columbia University Kingsmen (1949), the Jabberwocks of Brown University (1949), and the University of Rochester YellowJackets (1956). All-women a cappella groups followed shortly, frequently as a parody of the men's groups: the Smiffenpoofs of Smith College (1936), The Shwiffs of Connecticut College (The She-Whiffenpoofs, 1944), and The Chattertocks of Brown University (1951). A cappella groups exploded in popularity beginning in the 1990s, fueled in part by a change in style popularized by the Tufts University Beelzebubs and the Boston University Dear Abbeys. The new style used voices to emulate modern rock instruments, including vocal percussion/"beatboxing". Some larger universities now have multiple groups. Groups often join one another in on-campus concerts, such as the Georgetown Chimes' Cherry Tree Massacre, a 3-weekend a cappella festival held each February since 1975, where over a hundred collegiate groups have appeared, as well as International Quartet Champions The Boston Common and the contemporary commercial a cappella group Rockapella. Co-ed groups have produced many up-and-coming and major artists, including John Legend, an alumnus of the Counterparts at the University of Pennsylvania, and Sara Bareilles, an alumna of Awaken A Cappella at University of California, Los Angeles. Mira Sorvino is an alumna of the Harvard-Radcliffe Veritones of Harvard College where she had the solo on Only You by Yaz.

During what time period did continuously-singing groups grow?
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A: unanswerable

Problem: There are two major sports centers in Nanjing, Wutaishan Sports Center and Nanjing Olympic Sports Center. Both of these two are comprehensive sports centers, including stadium, gymnasium, natatorium, tennis court, etc. Wutaishan Sports Center was established in 1952 and it was one of the oldest and most advanced stadiums in early time of People's Republic of China.
What is special about Wutaishan Sports Center, from a historical perspective?
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Answer: it was one of the oldest and most advanced stadiums in early time of People's Republic of China.

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Other notable places include Elizabeth Fort, the Cork Opera House, Christ Church on South Main Street (now the Triskel Arts Centre and original site of early Hiberno-Norse church), St Mary's Dominican Church on Popes Quay and Fitzgerald's Park to the west of the city, which contains the Cork Public Museum. Other popular tourist attractions include the grounds of University College Cork, through which the River Lee flows, the Women's Gaol at Sundays Well (now a heritage centre) and the English Market. This covered market traces its origins back to 1610, and the present building dates from 1786.
What park does the River Lee flow through?
A: unanswerable

Context and question: The foundation stone of the city was laid by George V, Emperor of India during the Delhi Durbar of 1911. It was designed by British architects, Sir Edwin Lutyens and Sir Herbert Baker. The new capital was inaugurated on 13 February 1931, by India's Viceroy Lord Irwin.
In what year was the foundation stone of New Delhi laid?
Answer: 1911

Question: The Late Middle Ages represented a period of upheaval in Europe. The epidemic known as the Black Death and an associated famine caused demographic catastrophe in Europe as the population plummeted. Dynastic struggles and wars of conquest kept many of the states of Europe at war for much of the period. In the Balkans, the Ottoman Empire, a Turkish state originating in Anatolia, encroached steadily on former Byzantine lands, culminating in the Fall of Constantinople in 1453.
Is there an answer to this question: When did the Ottoman Empire liberate Constantinople from the Balkans?

Answer: unanswerable

Question: The port was the point of departure for the Pilgrim Fathers aboard Mayflower in 1620. In 1912, the RMS Titanic sailed from Southampton. Four in five of the crew on board the vessel were Sotonians, with about a third of those who perished in the tragedy hailing from the city. Southampton was subsequently the home port for the transatlantic passenger services operated by Cunard with their Blue Riband liner RMS Queen Mary and her running mate RMS Queen Elizabeth. In 1938, Southampton docks also became home to the flying boats of Imperial Airways. Southampton Container Terminals first opened in 1968 and has continued to expand.
Is there an answer to this question: How many crew members out of every five on the RMS Titanic were Sotonians?

Answer:
Four