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On the other hand, Mexico City is also home to large communities of expatriates and immigrants, most notably from the rest of North America (U.S. and Canada), from South America (mainly from Argentina and Colombia, but also from Brazil, Chile, Uruguay and Venezuela), from Central America and the Caribbean (mainly from Cuba, Guatemala, El Salvador, Haiti and Honduras); from Europe (mainly from Spain, Germany and Switzerland, but also from Czech Republic, Hungary, France, Italy, Ireland, the Netherlands, Poland and Romania), from the Middle East (mainly from Egypt, Lebanon and Syria); and recently from Asia-Pacific (mainly from China and South Korea). Historically since the era of New Spain, many Filipinos settled in the city and have become integrated in Mexican society. While no official figures have been reported, population estimates of each of these communities are quite significant.
What countries do most of the South American immigrants come from?
A: Argentina and Colombia

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Also labeled an Orphist by Apollinaire, Marcel Duchamp was responsible for another extreme development inspired by Cubism. The ready-made arose from a joint consideration that the work itself is considered an object (just as a painting), and that it uses the material detritus of the world (as collage and papier collé in the Cubist construction and Assemblage). The next logical step, for Duchamp, was to present an ordinary object as a self-sufficient work of art representing only itself. In 1913 he attached a bicycle wheel to a kitchen stool and in 1914 selected a bottle-drying rack as a sculpture in its own right.
What was Duchamp not responsible for?
A: unanswerable

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Sanskrit, as defined by Pāṇini, evolved out of the earlier Vedic form. The present form of Vedic Sanskrit can be traced back to as early as the second millennium BCE (for Rig-vedic). Scholars often distinguish Vedic Sanskrit and Classical or "Pāṇinian" Sanskrit as separate dialects. Though they are quite similar, they differ in a number of essential points of phonology, vocabulary, grammar and syntax. Vedic Sanskrit is the language of the Vedas, a large collection of hymns, incantations (Samhitas) and theological and religio-philosophical discussions in the Brahmanas and Upanishads. Modern linguists consider the metrical hymns of the Rigveda Samhita to be the earliest, composed by many authors over several centuries of oral tradition. The end of the Vedic period is marked by the composition of the Upanishads, which form the concluding part of the traditional Vedic corpus; however, the early Sutras are Vedic, too, both in language and content.
What is Vedic Sanskrit meant to be used as?
A: the Vedas

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Disadvantages of electric traction include high capital costs that may be uneconomic on lightly trafficked routes; a relative lack of flexibility since electric trains need electrified tracks or onboard supercapacitors and charging infrastructure at stations; and a vulnerability to power interruptions. Different regions may use different supply voltages and frequencies, complicating through service. The limited clearances available under catenaries may preclude efficient double-stack container service. The lethal voltages on contact wires and third rails are a safety hazard to track workers, passengers and trespassers. Overhead wires are safer than third rails, but they are often considered unsightly.
Why overhead wires are not being widely used?
A:
considered unsightly.