Problem: Given the question: Extract the answer to the question from the following context. Question: what type of string is mentioned third to last? Context: Samuel Adelstein described the Lombardi mandolin in 1893 as wider and shorter than the Neapolitan mandolin, with a shallower back and a shorter and wider neck, with six single strings to the regular mandolin's set of 4. The Lombardi was tuned C, D, A, E, B, G. The strings were fastened to the bridge like a guitar's. There were 20 frets, covering three octaves, with an additional 5 notes. When Adelstein wrote, there were no nylon strings, and the gut and single strings "do not vibrate so clearly and sweetly as the double steel string of the Neapolitan."
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The answer is:
gut


Problem: Given the question: Extract the answer to the question from the following context. Question: What was at the centre of the atomic bomb? Context: Von Neumann's principal contribution to the atomic bomb was in the concept and design of the explosive lenses needed to compress the plutonium core of the Fat Man weapon that was later dropped on Nagasaki. While von Neumann did not originate the "implosion" concept, he was one of its most persistent proponents, encouraging its continued development against the instincts of many of his colleagues, who felt such a design to be unworkable. He also eventually came up with the idea of using more powerful shaped charges and less fissionable material to greatly increase the speed of "assembly".
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The answer is:
plutonium


Problem: Given the question: Extract the answer to the question from the following context. Question: This age group would be considered the geriatric millennial's comparatively coming in last in terms of population composition? Context: There are 119,500 males within the city and 117,400 females. The 20–24 age range is the most populous, with an estimated 32,300 people falling in this age range. Next largest is the 25–29 range with 24,700 people and then 30–34 years with 17,800. By population, Southampton is the largest monocentric city in the South East England region and the second largest on the South Coast after Plymouth.
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The answer is:
30–34