Problem: Mandolin:

Mandolin has also been used in blues music, most notably by Ry Cooder, who performed outstanding covers on his very first recordings, Yank Rachell, Johnny "Man" Young, Carl Martin, and Gerry Hundt. Howard Armstrong, who is famous for blues violin, got his start with his father's mandolin and played in string bands similar to the other Tennessee string bands he came into contact with, with band makeup including "mandolins and fiddles and guitars and banjos. And once in a while they would ease a little ukulele in there and a bass fiddle." Other blues players from the era's string bands include Willie Black (Whistler And His Jug Band), Dink Brister, Jim Hill, Charles Johnson, Coley Jones (Dallas String Band), Bobby Leecan (Need More Band), Alfred Martin, Charlie McCoy (1909-1950), Al Miller, Matthew Prater, and Herb Quinn.

Who is the most popular blue music mandolinist?
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A: Ry Cooder

Problem: Neurotransmitters are chemicals that are released at synapses when an action potential activates themneurotransmitters attach themselves to receptor molecules on the membrane of the synapse's target cell, and thereby alter the electrical or chemical properties of the receptor molecules. With few exceptions, each neuron in the brain releases the same chemical neurotransmitter, or combination of neurotransmitters, at all the synaptic connections it makes with other neurons; this rule is known as Dale's principle. Thus, a neuron can be characterized by the neurotransmitters that it releases. The great majority of psychoactive drugs exert their effects by altering specific neurotransmitter systems. This applies to drugs such as cannabinoids, nicotine, heroin, cocaine, alcohol, fluoxetine, chlorpromazine, and many others.
Chemicals called neurotransmitters are released at what part of the brain?
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Answer: synapses

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Like most other regions of central and southern Germany, Thuringia has a significant industrial sector reaching back to the mid-19th-century industrialisation. The economic transition after the German reunification in 1990 led to the closure of most large-scale factories and companies, leaving small and medium-sized ones to dominate the manufacturing sector. Well-known industrial centres are Jena (a world centre for optical instruments with companies like Carl Zeiss, Schott and Jenoptik) and Eisenach, where BMW started its car production in the 1920s and an Opel factory is based today. The most important industrial branches today are engineering and metalworking, vehicle production and food industries. Especially the small and mid-sized towns in central and southwestern Thuringia (e.g. Arnstadt, Schmalkalden and Ohrdruf) are highly industrialised, whereas there are fewer industrial companies in the northern and eastern parts of the Land. Traditional industries like production of glass, porcelain and toys collapsed during the economic crises between 1930 and 1990.
Where in Thuringia are there no industrial companies?
A: unanswerable

Context and question: The most important crop in Tibet is barley, and dough made from barley flourcalled tsampais the staple food of Tibet. This is either rolled into noodles or made into steamed dumplings called momos. Meat dishes are likely to be yak, goat, or mutton, often dried, or cooked into a spicy stew with potatoes. Mustard seed is cultivated in Tibet, and therefore features heavily in its cuisine. Yak yogurt, butter and cheese are frequently eaten, and well-prepared yogurt is considered something of a prestige item. Butter tea is very popular to drink.
What are meat dumplings called?
Answer: unanswerable

Question: In the simplest case, a single connection is established to an upstream ISP and is used to transmit data to or from areas of the Internet beyond the home network; this mode of interconnection is often cascaded multiple times until reaching a tier 1 carrier. In reality, the situation is often more complex. ISPs with more than one point of presence (PoP) may have separate connections to an upstream ISP at multiple PoPs, or they may be customers of multiple upstream ISPs and may have connections to each one of them at one or more point of presence. Transit ISPs provide large amounts of bandwidth for connecting hosting ISPs and access ISPs.
Is there an answer to this question: What has the same connection to an upstream ISP?

Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
PS3's hardware has also been used to build supercomputers for high-performance computing. Fixstars Solutions sells a version of Yellow Dog Linux for PlayStation 3 (originally sold by Terra Soft Solutions). RapidMind produced a stream programming package for PS3, but were acquired by Intel in 2009. Also, on January 3, 2007, Dr. Frank Mueller, Associate Professor of Computer science at NCSU, clustered 8 PS3s. Mueller commented that the 256 MB of system RAM is a limitation for this particular application and is considering attempting to retrofit more RAM. Software includes: Fedora Core 5 Linux ppc64, MPICH2, OpenMP v 2.5, GNU Compiler Collection and CellSDK 1.1. As a more cost-effective alternative to conventional supercomputers, the U.S. military has purchased clusters of PS3 units for research purposes. Retail PS3 Slim units cannot be used for supercomputing, because PS3 Slim lacks the ability to boot into a third-party OS.
Who clustered 18 PS3s?
A:
unanswerable