Problem: Mexico City:

Mexico City is served by the Sistema de Transporte Colectivo, a 225.9 km (140 mi) metro system, which is the largest in Latin America. The first portions were opened in 1969 and it has expanded to 12 lines with 195 stations. The metro is one of the busiest in the world transporting approximately 4.5 million people every day, surpassed only by subway lines in Moscow (7.5 million), Tokyo (5.9 million), and New York City (5.1 million). It is heavily subsidized, and has some of the lowest fares in the world, each trip costing 5.00 pesos from 05:00 am to midnight. Several stations display pre-Columbian artifacts and architecture that were discovered during the metro's construction.[citation needed] However, the metro covers less than half of the total urban area. The Metro stations are also differentiated by the use of icons and glyphs which were proposed for people who could not read. The specific icons were developed based on historical (characters, sites, pre-Hispanic motifs), linguistic, symbolic (glyphs) or location references and has being emulated in further transportations alternatives in the City and in other Mexican cities. Mexico City is the only city in the world to use the icon reference and has become a popular culture trademark for the city.

When was the Mexico City metro system first opened?
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A: 1969


Problem: Lie groups are of fundamental importance in modern physics: Noether's theorem links continuous symmetries to conserved quantities. Rotation, as well as translations in space and time are basic symmetries of the laws of mechanics. They can, for instance, be used to construct simple models—imposing, say, axial symmetry on a situation will typically lead to significant simplification in the equations one needs to solve to provide a physical description.v[›] Another example are the Lorentz transformations, which relate measurements of time and velocity of two observers in motion relative to each other. They can be deduced in a purely group-theoretical way, by expressing the transformations as a rotational symmetry of Minkowski space. The latter serves—in the absence of significant gravitation—as a model of space time in special relativity. The full symmetry group of Minkowski space, i.e. including translations, is known as the Poincaré group. By the above, it plays a pivotal role in special relativity and, by implication, for quantum field theories. Symmetries that vary with location are central to the modern description of physical interactions with the help of gauge theory.
What measures the time and velocity of two observers?
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Answer: unanswerable


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
On 14 January 1858, an Italian refugee from Britain called Orsini attempted to assassinate Napoleon III with a bomb made in England. The ensuing diplomatic crisis destabilised the government, and Palmerston resigned. Derby was reinstated as prime minister. Victoria and Albert attended the opening of a new basin at the French military port of Cherbourg on 5 August 1858, in an attempt by Napoleon III to reassure Britain that his military preparations were directed elsewhere. On her return Victoria wrote to Derby reprimanding him for the poor state of the Royal Navy in comparison to the French one. Derby's ministry did not last long, and in June 1859 Victoria recalled Palmerston to office.
Who did Orsini try to assassinate?
A: Napoleon III


Context and question: Most of the space in the brain is taken up by axons, which are often bundled together in what are called nerve fiber tracts. A myelinated axon is wrapped in a fatty insulating sheath of myelin, which serves to greatly increase the speed of signal propagation. (There are also unmyelinated axons). Myelin is white, making parts of the brain filled exclusively with nerve fibers appear as light-colored white matter, in contrast to the darker-colored grey matter that marks areas with high densities of neuron cell bodies.
Axons grouped together are known as what?
Answer: nerve fiber tracts


Question: In general, Hokkien dialects have 5 to 7 phonemic tones. According to the traditional Chinese system, however, there are 7 to 9 "tones",[citation needed] more correctly termed tone classes since two of them are non-phonemic "entering tones" (see the discussion on Chinese tone). Tone sandhi is extensive. There are minor variations between the Quanzhou and Zhangzhou tone systems. Taiwanese tones follow the patterns of Amoy or Quanzhou, depending on the area of Taiwan. Many dialects have an additional phonemic tone ("tone 9" according to the traditional reckoning), used only in special or foreign loan words.
Is there an answer to this question: How many phonemic tones do Hokkien dialects have?

Answer: 5 to 7


QUES: While the original Xbox sold poorly in Japan, selling just 2 million units while it was on the market (between 2002 and 2005),[citation needed] the Xbox 360 sold even more poorly, selling only 1.5 million units from 2005 to 2011. Edge magazine reported in August 2011 that initially lackluster and subsequently falling sales in Japan, where Microsoft had been unable to make serious inroads into the dominance of domestic rivals Sony and Nintendo, had led to retailers scaling down and in some cases discontinuing sales of the Xbox 360 completely.

When did Edge report Sony sales were falling?
What is the answer?
ANS:
unanswerable