Problem: Incandescent light bulb:

The spectrum emitted by a blackbody radiator at temperatures of incandescent bulbs does not match the sensitivity characteristics of the human eye; the light emitted does not appear white, and most is not in the range of wavelengths at which the eye is most sensitive. Tungsten filaments radiate mostly infrared radiation at temperatures where they remain solid below 3,695 K (3,422 C; 6,191 F). Donald L. Klipstein explains it this way: "An ideal thermal radiator produces visible light most efficiently at temperatures around 6,300 C (6,600 K; 11,400 F). Even at this high temperature, a lot of the radiation is either infrared or ultraviolet, and the theoretical luminous efficacy (LER) is 95 lumens per watt." No known material can be used as a filament at this ideal temperature, which is hotter than the sun's surface. An upper limit for incandescent lamp luminous efficacy (LER) is around 52 lumens per watt, the theoretical value emitted by tungsten at its melting point.

What appears white to the human eye when it is emitted?
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A: unanswerable

Problem: Cuban immigrants in the 1960s brought the Cuban sandwich, medianoche, Cuban espresso, and croquetas, all of which have grown in popularity to all Miamians, and have become symbols of the city's varied cuisine. Today, these are part of the local culture, and can be found throughout the city in window cafes, particularly outside of supermarkets and restaurants. Restaurants such as Versailles restaurant in Little Havana is a landmark eatery of Miami. Located on the Atlantic Ocean, and with a long history as a seaport, Miami is also known for its seafood, with many seafood restaurants located along the Miami River, and in and around Biscayne Bay. Miami is also the home of restaurant chains such as Burger King, Tony Roma's and Benihana.
Along with Benihana and Burger King, what chain restaurant is headquartered in Miami?
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Answer: Tony Roma's

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In addition to the minimal units that can serve the purpose of differentiating meaning (the phonemes), phonology studies how sounds alternate, i.e. replace one another in different forms of the same morpheme (allomorphs), as well as, for example, syllable structure, stress, feature geometry, accent, and intonation.
What do phonemes differentiate?
A: meaning

Context and question: Hydrogen forms a vast array of compounds with carbon called the hydrocarbons, and an even vaster array with heteroatoms that, because of their general association with living things, are called organic compounds. The study of their properties is known as organic chemistry and their study in the context of living organisms is known as biochemistry. By some definitions, "organic" compounds are only required to contain carbon. However, most of them also contain hydrogen, and because it is the carbon-hydrogen bond which gives this class of compounds most of its particular chemical characteristics, carbon-hydrogen bonds are required in some definitions of the word "organic" in chemistry. Millions of hydrocarbons are known, and they are usually formed by complicated synthetic pathways, which seldom involve elementary hydrogen.
What is the form of hydrogen and carbon called?
Answer: hydrocarbons

Question: The most obvious link between modern and ancient Greeks is their language, which has a documented tradition from at least the 14th century BC to the present day, albeit with a break during the Greek Dark Ages (lasting from the 11th to the 8th century BC). Scholars compare its continuity of tradition to Chinese alone. Since its inception, Hellenism was primarily a matter of common culture and the national continuity of the Greek world is a lot more certain than its demographic. Yet, Hellenism also embodied an ancestral dimension through aspects of Athenian literature that developed and influenced ideas of descent based on autochthony. During the later years of the Eastern Roman Empire, areas such as Ionia and Constantinople experienced a Hellenic revival in language, philosophy, and literature and on classical models of thought and scholarship. This revival provided a powerful impetus to the sense of cultural affinity with ancient Greece and its classical heritage. The cultural changes undergone by the Greeks are, despite a surviving common sense of ethnicity, undeniable. At the same time, the Greeks have retained their language and alphabet, certain values and cultural traditions, customs, a sense of religious and cultural difference and exclusion, (the word barbarian was used by 12th-century historian Anna Komnene to describe non-Greek speakers), a sense of Greek identity and common sense of ethnicity despite the global political and social changes of the past two millennia.
Is there an answer to this question: How log did the age of darkness last for the Greeks ?

Answer: Greek Dark Ages (lasting from the 11th to the 8th century BC)

Science came to play a leading role in Enlightenment discourse and thought. Many Enlightenment writers and thinkers had backgrounds in the sciences and associated scientific advancement with the overthrow of religion and traditional authority in favour of the development of free speech and thought. Scientific progress during the Enlightenment included the discovery of carbon dioxide (fixed air) by the chemist Joseph Black, the argument for deep time by the geologist James Hutton, and the invention of the steam engine by James Watt. The experiments of Lavoisier were used to create the first modern chemical plants in Paris, and the experiments of the Montgolfier Brothers enabled them to launch the first manned flight in a hot-air balloon on 21 November 1783, from the Chateau de la Muette, near the Bois de Boulogne.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Who discovered carbon dioxide or fixed air?
Ah, so..
chemist Joseph Black