This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
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Question: Passage: Northwestern has several housing options, including both traditional residence halls and residential colleges which gather together students who have a particular intellectual interest in common. Among the residential colleges are the Residential College of Cultural and Community Studies (CCS), Ayers College of Commerce and Industry, Jones Residential College (Arts), and Slivka Residential College (Science and Engineering). Dorms include 1835 Hinman, Bobb-McCulloch, Foster-Walker complex (commonly referred to as Plex), and several more. In Winter 2013, 39% of undergraduates were affiliated with a fraternity or sorority. Northwestern recognizes 21 fraternities and 18 sororities. Question: How many fraternities does Northwestern recognize?

Answer: 21


Question: Passage: Multiracial Americans are Americans who have mixed ancestry of "two or more races". The term may also include Americans of mixed-race ancestry who self-identify with just one group culturally and socially (cf. the one-drop rule). In the 2010 US census, approximately 9 million individuals, or 2.9% of the population, self-identified as multiracial. There is evidence that an accounting by genetic ancestry would produce a higher number, but people live according to social and cultural identities, not DNA. Historical reasons, including slavery creating a racial caste and the European-American suppression of Native Americans, often led people to identify or be classified by only one ethnicity, generally that of the culture in which they were raised. Prior to the mid-20th century, many people hid their multiracial heritage because of racial discrimination against minorities. While many Americans may be biologically multiracial, they often do not know it or do not identify so culturally, any more than they maintain all the differing traditions of a variety of national ancestries. Question: Why did muticultural Americans hid their heritage?

Answer: many people hid their multiracial heritage because of racial discrimination against minorities


Question: Passage: Glaciers are broken into zones based on surface snowpack and melt conditions. The ablation zone is the region where there is a net loss in glacier mass. The equilibrium line separates the ablation zone and the accumulation zone; it is the altitude where the amount of new snow gained by accumulation is equal to the amount of ice lost through ablation. The upper part of a glacier, where accumulation exceeds ablation, is called the accumulation zone. In general, the accumulation zone accounts for 60–70% of the glacier's surface area, more if the glacier calves icebergs. Ice in the accumulation zone is deep enough to exert a downward force that erodes underlying rock. After a glacier melts, it often leaves behind a bowl- or amphitheater-shaped depression that ranges in size from large basins like the Great Lakes to smaller mountain depressions known as cirques. Question: Which glacial zone area reports a net-loss in glacial mass?

Answer:
ablation zone