Problem: Mandolin:

Instruments were marketed by teacher-dealers, much as the title character in the popular musical The Music Man. Often, these teacher-dealers conducted mandolin orchestras: groups of 4-50 musicians who played various mandolin family instruments. However, alongside the teacher-dealers were serious musicians, working to create a spot for the instrument in classical music, ragtime and jazz. Like the teacher-dealers, they traveled the U.S., recording records, giving performances and teaching individuals and mandolin orchestras. Samuel Siegel played mandolin in Vaudeville and became one of America's preeminent mandolinists. Seth Weeks was an African American who not only taught and performed in the United States, but also in Europe, where he recorded records. Another pioneering African American musician and director who made his start with a mandolin orchestra was composer James Reese Europe. W. Eugene Page toured the country with a group, and was well known for his mandolin and mandola performances. Other names include Valentine Abt, Samuel Adelstein, William Place, Jr., and Aubrey Stauffer.

What did these teacher-dealers often conduct?
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A: mandolin orchestras

Problem: The Queen addressed the United Nations for a second time in 2010, again in her capacity as Queen of all Commonwealth realms and Head of the Commonwealth. The UN Secretary General, Ban Ki-moon, introduced her as "an anchor for our age". During her visit to New York, which followed a tour of Canada, she officially opened a memorial garden for the British victims of the September 11 attacks. The Queen's visit to Australia in October 2011 her sixteenth visit since 1954 was called her "farewell tour" in the press because of her age.
How many British people died in the 9-11 attack?
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Answer: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Seattle's foreign-born population grew 40% between the 1990 and 2000 censuses. The Chinese population in the Seattle area has origins in mainland China, Hong Kong, Southeast Asia, and Taiwan. The earliest Chinese-Americans that came in the late 19th and early 20th centuries were almost entirely from Guangdong province. The Seattle area is also home to a large Vietnamese population of more than 55,000 residents, as well as over 30,000 Somali immigrants. The Seattle-Tacoma area is also home to one of the largest Cambodian communities in the United States, numbering about 19,000 Cambodian Americans, and one of the largest Samoan communities in the mainland U.S., with over 15,000 people having Samoan ancestry. Additionally, the Seattle area had the highest percentage of self-identified mixed-race people of any large metropolitan area in the United States, according to the 2000 United States Census Bureau. According to a 2012 HistoryLink study, Seattle's 98118 ZIP code (in the Columbia City neighborhood) was one of the most diverse ZIP Code Tabulation Areas in the United States.
How much did Seattle's foreign born population expand between 1990-2000?
A: 40%

Context and question: Prominent theatre companies in Oklahoma include, in the capital city, Oklahoma City Theatre Company, Carpenter Square Theatre, Oklahoma Shakespeare in the Park, and CityRep. CityRep is a professional company affording equity points to those performers and technical theatre professionals. In Tulsa, Oklahoma's oldest resident professional company is American Theatre Company, and Theatre Tulsa is the oldest community theatre company west of the Mississippi. Other companies in Tulsa include Heller Theatre and Tulsa Spotlight Theater. The cities of Norman, Lawton, and Stillwater, among others, also host well-reviewed community theatre companies.
What is the oldest resident professional theater company in Oklahoma?
Answer: American Theatre Company

Question: Richmond has a significant arts community, some of which is contained in formal public-supported venues, and some of which is more DIY, such as local privately owned galleries, and private music venues, nonprofit arts organizations, or organic and venueless arts movements (e.g., house shows, busking, itinerant folk shows). This has led to tensions, as the city Richmond City levied an "admissions tax" to fund large arts projects like CentreStage, leading to criticism that it is funding civic initiatives on the backs of the organic local culture. Traditional Virginian folk music, including blues, country, and bluegrass are also notably present, and play a large part in the annual Richmond Folk Festival. The following is a list of the more formal arts establishments (Companies, theaters, galleries, and other large venues) in Richmond:
Is there an answer to this question: Along with blues and bluegrass, what is a type of folk music traditional to Virginia?

Answer: country

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
This method involves coating LEDs of one color (mostly blue LEDs made of InGaN) with phosphors of different colors to form white light; the resultant LEDs are called phosphor-based or phosphor-converted white LEDs (pcLEDs). A fraction of the blue light undergoes the Stokes shift being transformed from shorter wavelengths to longer. Depending on the color of the original LED, phosphors of different colors can be employed. If several phosphor layers of distinct colors are applied, the emitted spectrum is broadened, effectively raising the color rendering index (CRI) value of a given LED.
What method involves coating LEDs of multiple color with phosphors of different colors?
A:
unanswerable