Problem: PlayStation 3:

PlayStation Network is the unified online multiplayer gaming and digital media delivery service provided by Sony Computer Entertainment for PlayStation 3 and PlayStation Portable, announced during the 2006 PlayStation Business Briefing meeting in Tokyo. The service is always connected, free, and includes multiplayer support. The network enables online gaming, the PlayStation Store, PlayStation Home and other services. PlayStation Network uses real currency and PlayStation Network Cards as seen with the PlayStation Store and PlayStation Home.

Does PlayStation Network use artificial or real currency for purchases?
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A: real


Problem: The team's commitment to contend was complete when Green made a midseason deal on June 15 to shore up the starting rotation due to injuries to Rick Reuschel (5–5) and Sanderson. The deal brought 1979 NL Rookie of the Year pitcher Rick Sutcliffe from the Cleveland Indians. Joe Carter (who was with the Triple-A Iowa Cubs at the time) and center fielder Mel Hall were sent to Cleveland for Sutcliffe and back-up catcher Ron Hassey (.333 with Cubs in 1984). Sutcliffe (5–5 with the Indians) immediately joined Sanderson (8–5 3.14), Eckersley (10–8 3.03), Steve Trout (13–7 3.41) and Dick Ruthven (6–10 5.04) in the starting rotation. Sutcliffe proceeded to go 16–1 for Cubs and capture the Cy Young Award.
Where had Rick Sutcliffe been before moving to the Cubs?
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Answer: the Cleveland Indians


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
A non-Greek origin of Apollo has long been assumed in scholarship. The name of Apollo's mother Leto has Lydian origin, and she was worshipped on the coasts of Asia Minor. The inspiration oracular cult was probably introduced into Greece from Anatolia, which is the origin of Sibyl, and where existed some of the oldest oracular shrines. Omens, symbols, purifications, and exorcisms appear in old Assyro-Babylonian texts, and these rituals were spread into the empire of the Hittites. In a Hittite text is mentioned that the king invited a Babylonian priestess for a certain "purification".
What origin was Leto?
A: Lydian


Context and question: In Europe, and other regions using the ISO 216 paper sizing system, the weight is expressed in grammes per square metre (g/m2 or usually just g) of the paper. Printing paper is generally between 60 g and 120 g. Anything heavier than 160 g is considered card. The weight of a ream therefore depends on the dimensions of the paper and its thickness.
What ISO sizing system does Europe use?
Answer: ISO 216


Question: Since the Three Kingdoms period, Nanjing has been an industrial centre for textiles and minting owing to its strategic geographical location and convenient transportation. During the Ming dynasty, Nanjing's industry was further expanded, and the city became one of the most prosperous cities in China and the world. It led in textiles, minting, printing, shipbuilding and many other industries, and was the busiest business center in East Asia. Textiles boomed particularly in Qing dynasty, the industry created around 200 thousand jobs and there were about 50 thousand satin machines in the city in 18th and 19th century.
Is there an answer to this question: During what dynasty was Nanjing the biggest business center in all of East Asia?

Answer: Ming


NARA also maintains the Presidential Library system, a nationwide network of libraries for preserving and making available the documents of U.S. presidents since Herbert Hoover. The Presidential Libraries include:
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What did Herbert Hoover maintain?
Ah, so..
unanswerable