Problem: Valencia:

Public transport is provided by the Ferrocarrils de la Generalitat Valenciana (FGV), which operates the Metrovalencia and other rail and bus services. The Estació del Nord (North Station) is the main railway terminus in Valencia. A new temporary station, Estación de València-Joaquín Sorolla, has been built on land adjacent to this terminus to accommodate high speed AVE trains to and from Madrid, Barcelona, Seville and Alicante. Valencia Airport is situated 9 km (5.6 mi) west of Valencia city centre. Alicante Airport is situated about 170 km (110 mi) south of Valencia.

What is the main train station in Valencia?
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A: Estació del Nord


Problem: Nasser played a significant part in the strengthening of African solidarity in the late 1950s and early 1960s, although his continental leadership role had increasingly passed to Algeria since 1962. During this period, Nasser made Egypt a refuge for anti-colonial leaders from several African countries and allowed the broadcast of anti-colonial propaganda from Cairo. Beginning in 1958, Nasser had a key role in the discussions among African leaders that led to the establishment of the Organisation of African Unity (OAU) in 1963.
What year was the OAU formed?
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Answer: 1963


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Cities not served by road, sea, or river can be reached only by air, foot, dogsled, or snowmachine, accounting for Alaska's extremely well developed bush air services—an Alaskan novelty. Anchorage and, to a lesser extent Fairbanks, is served by many major airlines. Because of limited highway access, air travel remains the most efficient form of transportation in and out of the state. Anchorage recently completed extensive remodeling and construction at Ted Stevens Anchorage International Airport to help accommodate the upsurge in tourism (in 2012-2013, Alaska received almost 2 million visitors).
How many visitors came to Alaska between 2012-2014?
A: unanswerable


Context and question: Like the reptiles, birds are primarily uricotelic, that is, their kidneys extract nitrogenous waste from their bloodstream and excrete it as uric acid instead of urea or ammonia through the ureters into the intestine. Birds do not have a urinary bladder or external urethral opening and (with exception of the ostrich) uric acid is excreted along with feces as a semisolid waste. However, birds such as hummingbirds can be facultatively ammonotelic, excreting most of the nitrogenous wastes as ammonia. They also excrete creatine, rather than creatinine like mammals. This material, as well as the output of the intestines, emerges from the bird's cloaca. The cloaca is a multi-purpose opening: waste is expelled through it, most birds mate by joining cloaca, and females lay eggs from it. In addition, many species of birds regurgitate pellets. Males within Palaeognathae (with the exception of the kiwis), the Anseriformes (with the exception of screamers), and in rudimentary forms in Galliformes (but fully developed in Cracidae) possess a penis, which is never present in Neoaves. The length is thought to be related to sperm competition. When not copulating, it is hidden within the proctodeum compartment within the cloaca, just inside the vent. The digestive system of birds is unique, with a crop for storage and a gizzard that contains swallowed stones for grinding food to compensate for the lack of teeth. Most birds are highly adapted for rapid digestion to aid with flight. Some migratory birds have adapted to use protein from many parts of their bodies, including protein from the intestines, as additional energy during migration.
How do most birds mate?
Answer: by joining cloaca


Question: Different linguists therefore take different approaches to the problem of assigning sounds to phonemes. For example, they differ in the extent to which they require allophones to be phonetically similar. There are also differing ideas as to whether this grouping of sounds is purely a tool for linguistic analysis, or reflects an actual process in the way the human brain processes a language.
Is there an answer to this question: What are assigned to phonemes by different linguists?

Answer: sounds


Color in glass may be obtained by addition of electrically charged ions (or color centers) that are homogeneously distributed, and by precipitation of finely dispersed particles (such as in photochromic glasses). Ordinary soda-lime glass appears colorless to the naked eye when it is thin, although iron(II) oxide (FeO) impurities of up to 0.1 wt% produce a green tint, which can be viewed in thick pieces or with the aid of scientific instruments. Further FeO and Cr2O3 additions may be used for the production of green bottles. Sulfur, together with carbon and iron salts, is used to form iron polysulfides and produce amber glass ranging from yellowish to almost black. A glass melt can also acquire an amber color from a reducing combustion atmosphere. Manganese dioxide can be added in small amounts to remove the green tint given by iron(II) oxide. When used in art glass or studio glass is colored using closely guarded recipes that involve specific combinations of metal oxides, melting temperatures and 'cook' times. Most colored glass used in the art market is manufactured in volume by vendors who serve this market although there are some glassmakers with the ability to make their own color from raw materials.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Charged ions can be used to produce what in glass?
Ah, so..
Color