Question: "Why were 1,500 extras required?"  Context: "With filming completed in Rome, production moved to Mexico City in late March to shoot the film's opening sequence, with scenes to include the Day of the Dead festival filmed in and around the Zócalo and the Centro Histórico district. The planned scenes required the city square to be closed for filming a sequence involving a fight aboard a Messerschmitt-Bölkow-Blohm Bo 105 helicopter flown by stunt pilot Chuck Aaron, which called for modifications to be made to several buildings to prevent damage. This particular scene in Mexico required 1,500 extras, 10 giant skeletons and 250,000 paper flowers. Reports in the Mexican media added that the film's second unit would move to Palenque in the state of Chiapas, to film aerial manoeuvres considered too dangerous to shoot in an urban area."  Answer:
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Answer: for filming a sequence involving a fight aboard a Messerschmitt-Bölkow-Blohm Bo 105 helicopter


Question: "What unmixed  races were included in the census?"  Context: "Historically, and since pre-Hispanic times, the Valley of Anahuac has been one of the most densely populated areas in Mexico. When the Federal District was created in 1824, the urban area of Mexico City extended approximately to the area of today's Cuauhtémoc borough. At the beginning of the 20th century, the elites began migrating to the south and west and soon the small towns of Mixcoac and San Ángel were incorporated by the growing conurbation. According to the 1921 census, 54.78% of the city's population was considered Mestizo (Indigenous mixed with European), 22.79% considered European, and 18.74% considered Indigenous. This was the last Mexican Census which asked people to self-identify themselves with an heritage other than Amerindian. However, the census had the particularity that, unlike racial/ethnic census in other countries, it was focused in the perception of cultural heritage rather than in a racial perception, leading to a good number of white people to identify with "Mixed heritage" due cultural influence. In 1921, Mexico City had less than one million inhabitants."  Answer:
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Answer: 22.79% considered European, and 18.74% considered Indigenous


Question: "what is Porto?"  Context: "Tourist hotspots in Portugal are Lisbon, Algarve, Madeira, Porto and the city of Coimbra, also, between 4-5 million religious pilgrims visit Fátima each year, where apparitions of the Blessed Virgin Mary to three shepherd children reportedly took place in 1917. The Sanctuary of Fátima is one of the largest Roman Catholic shrines in the world. The Portuguese government continues to promote and develop new tourist destinations, such as the Douro Valley, the island of Porto Santo, and Alentejo. Lisbon is the 16th European city which attracts the most tourists (with seven million tourists occupying the city's hotels in 2006, a number that grew 11.8% compared to previous year). Lisbon in recent years surpassed the Algarve as the leading tourist region in Portugal. Porto and Northern Portugal, especially the urban areas north of Douro River valley, was the tourist destination which grew most (11.9%) in 2006, surpassing Madeira (in 2010), as the third most visited destination.[citation needed]"  Answer:
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Answer:
Tourist hotspots