Q: Question: "What is the system known for?" Context: "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." Answer:
A: is the largest in Latin America

Q: Question: "Hypertension is an increased risk related to what?" Context: "Shift-work or chronic jet-lag have profound consequences on circadian and metabolic events in the body. Animals that are forced to eat during their resting period show increased body mass and altered expression of clock and metabolic genes.[medical citation needed] In humans, shift-work that favors irregular eating times is associated with altered insulin sensitivity and higher body mass. Shift-work also leads to increased metabolic risks for cardio-metabolic syndrome, hypertension, inflammation." Answer:
A: Shift-work

Q: Question: "When did house music peak in popularity?" Context: "In the late 1980s, many local Chicago house music artists suddenly found themselves presented with major label deals. House music proved to be a commercially successful genre and a more mainstream pop-based variation grew increasingly popular. Artists and groups such as Madonna, Janet Jackson, Paula Abdul, Aretha Franklin, Bananarama, Diana Ross, Tina Turner, Whitney Houston, Steps, Kylie Minogue, Bjork, and C+C Music Factoryhave all incorporated the genre into some of their work. After enjoying significant success in the early to mid-90s, house music grew even larger during the second wave of progressive house (19992001). The genre has remained popular and fused into other popular subgenres, for example, G-house, Deep House, Tech House and Bass House. As of 2015, house music remains extremely popular in both clubs and in the mainstream pop scene while retaining a foothold on underground scenes across the globe.[citation needed]" Answer:
A: during the second wave of progressive house (19992001)

Q: Question: "Which Canadian city harbors a Somali population and begins with the letter H?" Context: "Civil strife in the early 1990s greatly increased the size of the Somali diaspora, as many of the best educated Somalis left for the Middle East, Europe and North America. In Canada, the cities of Toronto, Ottawa, Calgary, Edmonton, Montreal, Vancouver, Winnipeg and Hamilton all harbor Somali populations. Statistics Canada's 2006 census ranks people of Somali descent as the 69th largest ethnic group in Canada." Answer:
A:
Hamilton