In this task, you are given a set of context paragraphs, some supporting facts and an answer of a question. Your task is to generate question for given answer based on set of context paragraphs, supporting facts and an answer.

Let me give you an example: Context_1 : Charles Edward Ives ( ; October 20, 1874May 19, 1954) was an American modernist composer. He is one of the first American composers of international renown, though his music was largely ignored during his life, and many of his works went unperformed for many years. Over time, he came to be regarded as an "American original". He combined the American popular and church-music traditions of his youth with European art music, and was among the first composers to engage in a systematic program of experimental music, with musical techniques including polytonality, polyrhythm, tone clusters, aleatory elements, and quarter tones, foreshadowing many musical innovations of the 20th century. Context_2 : Daniel Evan Freeman (born 27 April 1959) is an American musicologist who specializes in European art music of the eighteenth century, in particular the musical culture of eighteenth-century Prague and the Bohemian lands. He is also active as a pianist and music editor. Context_3 : Art music (also known as Western classical music, cultivated music, serious music, canonic music, and more flippantly, real music or normal music) is an umbrella term that refers to musical traditions, implying advanced structural and theoretical considerations and a written musical tradition. "Serious" or "cultivated" music are terms frequently used as a contrast for ordinary, everyday music (popular and folk music, also called "vernacular music"). After the 20th century, art music was divided into two extensions: "serious music" and "light music". Context_4 : In the history of European art music, the term "common practice period" refers to the era between the formation and the dissolution of the tonal system. Though there are no exact dates for this phenomenon, most features of the common-practice period persisted from the mid to late baroque period, through the Classical and Romantic periods, or roughly from around 1650 to 1900. While certain prevailing patterns and conventions characterize the music of this period, the time period also saw considerable stylistic evolution. Some conventions evolved during this period that were rarely employed at other times during what may still be labeled "common practice" (for example, Sonata Form). Thus, the dates 16501900 are necessarily nebulous and arbitrary borders that depend on context. The most important unifying feature through this time period concerns a harmonic language to which modern music theorists can apply Roman numeral analysis. Context_5 : The Festival Oude Muziek Utrecht ("Utrecht Early Music Festival") is an annual music festival that showcases and celebrates early European art music. The ten-day festival takes place in the Dutch city of Utrecht, and begins in August. The programme comprises concerts, activities, lectures, exhibitions, and a symposium. Context_6 : Assaf Shelleg (Hebrew: ), is a musicologist and pianist, a senior lecturer of musicology at The Hebrew University of Jerusalem. He was previously the Schusterman Visiting Assistant Professor of Musicology and Jewish Studies in the Department of Religious Studies at the University of Virginia (201114), and had taught prior to that as the visiting Efroymson Scholar in the Jewish, Islamic & Near Eastern Languages and Cultures Department at Washington University in St. Louis (200911). Shelleg specializes in twentieth-century Jewish and Israeli art music and has published in some of the leading journals in both musicology and Israel Studies on topics ranging from the historiography of modern Jewish art music to the theological networks of Israeli art music. Shelleg's book, "Jewish Contiguities and the Soundtrack of Israeli History", appeared in November 2014 with Oxford University Press. The book studies the emergence of modern Jewish art music in central and Western Europe (1910s-1930s) and its translocation to Palestine/Israel (1930s-1970s), exposing the legacies of European antisemitism and religious Judaism in the making of Israeli art music. Moving to consider the dislocation of modern Jewish art music the book examines the paradoxes embedded in a Zionist national culture whose rhetoric negated its pasts, only to mask process of hybridizations enchained by older legacies. "Jewish Contiguities" has won the 2015 Engle Prize for the study of Hebrew Music, and the 2016 Jordan Schnitzer Book Award. Context_7 : Vocal harmony is a style of vocal music in which a consonant note or notes are simultaneously sung as a main melody in a predominantly homophonic texture. Vocal harmonies are used in many subgenres of European art music, including Classical choral music and opera and in the popular styles from many Western cultures ranging from folk songs and musical theater pieces to rock ballads. In the simplest style of vocal harmony, the main vocal melody is supported by a single backup vocal line, either at a pitch which is above or below the main vocal line, often in thirds or sixths which fit in with the chord progression used in the song. In more complex vocal harmony arrangements, different backup singers may sing two or even three other notes at the same time as each of the main melody notes, mostly with consonant, pleasing-sounding thirds, sixths, and fifths (although dissonant notes may be used as short passing notes). Context_8 : David Wallis Reeves (February 14, 1838 March 8, 1900), also known as D. W. Reeves or Wally Reeves, was an American composer, cornetist, and bandleader. He developed the American march style, later made famous by the likes of John Philip Sousa, and his innovations include adding a countermelody to the American march form in 1876. Sousa called Reeves "The Father of Band Music in America", and stated he wished he himself had written Reeves' "Second Regiment Connecticut National Guard March". Charles Ives also borrowed from the "Second Connecticut" on four occasions. Context_9 : "Indian classical music is one of many forms of art music that have their roots in particular regional cultures. For other "classical" and art music traditions, see List of classical and art music traditions." Context_10 : Progressive music is music that subverts genre and expands stylistic boundaries outwards. Rooted in the idea of a cultural alternative, musical progressiveness embodies a continuous move between explicit and implicit references to genres and strategies derived from various cultural domains, such as European art music, Celtic folk, West Indian, or African. The word "progressive" comes from the basic concept of "progress", which refers to development and growth by accumulation, and is often deployed in numerous music genres such as progressive country, progressive folk, progressive jazz, and (most significantly) progressive rock. fact_1 : Charles Ives also borrowed from the "Second Connecticut" on four occasions. fact_2 : Charles Edward Ives ( ; October 20, 1874May 19, 1954) was an American modernist composer. fact_3 : He combined the American popular and church-music traditions of his youth with European art music, and was among the first composers to engage in a systematic program of experimental music, with musical techniques including polytonality, polyrhythm, tone clusters, aleatory elements, and quarter tones, foreshadowing many musical innovations of the 20th century. Answer: 1874May
The answer to this example can be: What is the birthyear of the American composer that borrowed from "Second Connecticut" on four occasions and combined American popular and church-music traditions with European art music?
Here is why: From the fact_1 from context _8, and fact _2 and fact _3 from context _1, we can arrive at 1874 May which is accurate answer of generated question.

OK. solve this:
Context_1 : The conservation and restoration of vinyl discs refers to the preventive measures taken to defend against damage and slow degradation, and to maintain fidelity of singles, 12" singles, EP, LP in 45 or 33 rpm disc recordings. LPs are most often in the 12" format, although very early vinyl recordings were 10". Vinyl LP preservation is generally considered separate from conservation, which refers to the repair and stabilization of individual discs. Commonly practiced in major sound archives and research libraries that house large collections of audio recordings, it is also frequently followed by audiophiles and home record collectors. Because vinyla virtually unbreakable light plastic made up of polyvinyl chloride acetate copolymer, or PVCis considered the most stable of analog recording media, it is seen as less a concern for deterioration than earlier sound recordings made from more fragile materials such as acetate, vulcanite, or shellac. This hardly means that vinyl recordings are infallible, however, and researchboth expert and evidentialhas shown that the way in which discs are handled and cared for can have a profound effect on their longevity. Though some 45s (7"s) are also made from vinyl, many of them are actually polystyrenea more fragile medium that is prone to fracturing from internal stress. Still, many of the recommendations for the care of vinyl LPs can be applied to 45s. Context_2 : Vinyl acetate is an organic compound with the formula CHCOCHCH. A colorless liquid with a pungent odor, it is the precursor to polyvinyl acetate, an important polymer in industry. Unlike many other acetate esters, the odor of vinyl acetate is thoroughly disagreeable and is not used to any substantial degree as an odorant. Context_3 : Wacker Chemie AG is a worldwide operating company in the chemical business, founded 1914. The company is controlled by the Wacker family holding more than 50 percent of the shares. The corporation is operating more than 25 production sites in Europe, Asia, and the Americas. The product range includes silicone rubbers, polymer products like ethylene vinyl acetate redispersible polymer powder, chemical materials, polysilicon and wafers for semiconductor industry. The company sells its products in more than 100 countries. As of 31 December 2015, 16,972 employees have been with Wacker. Corporate annual sales in 2015 were about 5,3 billion Euros, up 10% compared to 2014. Context_4 : Polyketones are a family of high-performance thermoplastic polymers. The polar ketone groups in the polymer backbone of these materials gives rise to a strong attraction between polymer chains, which increases the material's melting point (255C for copolymer (carbon monoxide ethylene), 220C for terpolymer (carbon monoxide, ethylene, propylene). Trade names include Carilon, Karilon, Akrotek, and Schulaketon. Such materials also tend to resist solvents and have good mechanical properties. Unlike many other engineering plastics, aliphatic polyketones such as Shell Chemicals' Carilon are relatively easy to synthesize and can be derived from inexpensive monomers. Carilon is made with a palladium(II) catalyst from ethylene and carbon monoxide. A small fraction of the ethylene is generally replaced with propylene to reduce the melting point somewhat. Shell Chemical commercially launched Carilon thermoplastic polymer in the U.S.in 1996, but discontinued it in 2000. SRI International offers Carilon thermoplastic polymers. Hyosung announced that they would launch production in 2015 Context_5 : Ethylene-vinyl acetate (EVA), also known as poly (ethylene-vinyl acetate) (PEVA), is the copolymer of ethylene and vinyl acetate. The weight percent vinyl acetate usually varies from 10 to 40%, with the remainder being ethylene. Context_6 : Solutia Inc. is a global manufacturer of performance materials and specialty chemicals including polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and thermoplastic polyurethane (TPU) interlayers for laminated glass, aftermarket window films, protective barrier and conductive films, and rubber processing chemicals, used in architectural, automotive, alternative energy, electronic devices, consumer and industrial applications. The company was formed on September 1, 1997, as a divestiture of the Monsanto Company chemical business. In July 2012, the company was acquired by Eastman Chemical Company. Context_7 : EPDM rubber (ethylene propylene diene monomer (M-class) rubber), a type of synthetic rubber, is an elastomer characterized by a wide range of applications. The "M" refers to its classification in ASTM standard D-1418; the "M" class includes rubbers having a saturated chain of the polymethylene type. Dienes currently used in the manufacture of EPDM rubbers are dicyclopentadiene (DCPD), ethylidene norbornene (ENB), and vinyl norbornene (VNB). EPDM rubber is closely related to ethylene propylene rubber: ethylene propylene rubber is a copolymer of ethylene and propylene, whereas EPDM rubber is a terpolymer of ethylene, propylene, and a diene-component. Context_8 : Nanofibers are fibers with diameters in the nanometer range. Nanofibers can be generated from different polymers and hence have different physical properties and application potentials. Examples of natural polymers include collagen, cellulose, silk fibroin, keratin, gelatin and polysaccharides such as chitosan and alginate. Examples of synthetic polymers include poly(lactic acid) (PLA), polycaprolactone (PCL), polyurethane (PU), poly(lactic-co-glycolic acid) (PLGA), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and poly(ethylene-co-vinylacetate) (PEVA). Polymer chains are connected via covalent bonds. The diameters of nanofibers depend on the type of polymer used and the method of production. All polymer nanofibers are unique for their large surface area-to-volume ratio, high porosity, appreciable mechanical strength, and flexibility in functionalization compared to their microfiber counterparts. Context_9 : Ethylene vinyl alcohol (EVOH) is a formal copolymer of ethylene and vinyl alcohol. Because the latter monomer mainly exists as its tautomer acetaldehyde, the copolymer is prepared by polymerization of ethylene and vinyl acetate to give the ethylene vinyl acetate (EVA) copolymer followed by hydrolysis. EVOH copolymer is defined by the mole % ethylene content: lower ethylene content grades have higher barrier properties; higher ethylene content grades have lower temperatures for extrusion. Context_10 : Polyvinyl chloride acetate (PVCA) is a thermoplastic copolymer of vinyl chloride and vinyl acetate. It is used in the manufacture of electrical insulation, of protective coverings (including garments), and of credit cards and swipe cards. fact_1 : Examples of synthetic polymers include poly(lactic acid) (PLA), polycaprolactone (PCL), polyurethane (PU), poly(lactic-co-glycolic acid) (PLGA), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and poly(ethylene-co-vinylacetate) (PEVA). fact_2 : Ethylene-vinyl acetate (EVA), also known as poly (ethylene-vinyl acetate) (PEVA), is the copolymer of ethylene and vinyl acetate. Answer: Ethylene-vinyl acetate
Answer:
What copolymer of ethylene and vinyl acetate can nanofibers be made of?