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The 100th meridian roughly corresponds with the line that divides the Great Plains into an area that receive 20 inches (510 millimetres) or more of rainfall per year and an area that receives less than 20 in (510 mm). In this context, the High Plains, as well as Southern Alberta, south-western Saskatchewan and Eastern Montana are mainly semi hot steppe land and are generally characterised by rangeland or marginal farmland. The region (especially the High Plains) is periodically subjected to extended periods of drought; high winds in the region may then generate devastating dust storms. The eastern Great Plains near the eastern boundary falls in the humid subtropical climate zone in the southern areas, and the northern and central areas fall in the humid continental climate.
What meridian comprises the southern edge of the Great Plains?
A: unanswerable

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True exhibition games between opposing colleges at the highest level do not exist in college football; due to the importance of opinion polling in the top level of college football, even exhibition games would not truly be exhibitions because they could influence the opinions of those polled. Intramural games are possible because a team playing against itself leaves little ability for poll participants to make judgments, and at levels below the Football Bowl Subdivision (FBS), championships are decided by objective formulas and thus those teams can play non-league games without affecting their playoff hopes.
What consideration is more important for college teams than exhibition games?
A: opinion polling

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While Harkness' original colleges were Georgian Revival or Collegiate Gothic in style, two colleges constructed in the 1960s, Morse and Ezra Stiles Colleges, have modernist designs. All twelve college quadrangles are organized around a courtyard, and each has a dining hall, courtyard, library, common room, and a range of student facilities. The twelve colleges are named for important alumni or significant places in university history. In 2017, the university expects to open two new colleges near Science Hill.
What are Yale's colleges encircled by?
A: unanswerable

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The World Bank has sponsored a project to curb air pollution through public transport improvements and the Mexican government has started shutting down polluting factories. They have phased out diesel buses and mandated new emission controls on new cars; since 1993 all new cars must be fitted with a catalytic converter, which reduces the emissions released. Trucks must use only liquefied petroleum gas (LPG). Also construction of an underground rail system was begun in 1968 in order to help curb air pollution problems and alleviate traffic congestion. Today it has over 201 km (125 mi) of track and carries over 5 million people every day. Fees are kept low to encourage use of the system and during rush hours the crush is so great, that authorities have reserved a special carriage specifically for women. Due to these initiatives and others, the air quality in Mexico City has begun to improve, with the air becoming cleaner since 1991, when the air quality was declared to be a public health risk for 355 days of the year.[citation needed]
What is one way the government helps with the "Crush" of the rush hour riding of the subway system?
A:
reserved a special carriage specifically for women