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: Between 2000 and 2004 an average of 478 crimes were reported each day in Mexico City; however, the actual crime rate is thought to be much higher "since most people are reluctant to report crime". Under policies enacted by Mayor Marcelo Ebrard between 2009 and 2011, Mexico City underwent a major security upgrade with violent and petty crime rates both falling significantly despite the rise in violent crime in other parts of the country. Some of the policies enacted included the installation of 11,000 security cameras around the city and a very large expansion of the police force. Mexico City has one of the world's highest police officer-to-resident ratios, with one uniformed officer per 100 citizens. Question: What Mexican mayor tried to crack down on crime immensely?

Answer: Marcelo Ebrard

Question: Passage: The word phonology comes from the Greek , phone, "voice, sound," and the suffix -logy (which is from Greek , logos, "word, speech, subject of discussion"). Definitions of the term vary. Nikolai Trubetzkoy in Grundzuge der Phonologie (1939) defines phonology as "the study of sound pertaining to the system of language," as opposed to phonetics, which is "the study of sound pertaining to the act of speech" (the distinction between language and speech being basically Saussure's distinction between langue and parole). More recently, Lass (1998) writes that phonology refers broadly to the subdiscipline of linguistics concerned with the sounds of language, while in more narrow terms, "phonology proper is concerned with the function, behavior and organization of sounds as linguistic items." According to Clark et al. (2007), it means the systematic use of sound to encode meaning in any spoken human language, or the field of linguistics studying this use. Question: Who in 1939 defined phonology?

Answer: Nikolai Trubetzkoy

Question: Passage: The areas that are not arid and receive high precipitation experience periodic flooding from rapid snowmelt and runoff. The mean precipitation in the Alps ranges from a low of 2,600 mm (100 in) per year to 3,600 mm (140 in) per year, with the higher levels occurring at high altitudes. At altitudes between 1,000 and 3,000 m (3,281 and 9,843 ft), snowfall begins in November and accumulates through to April or May when the melt begins. Snow lines vary from 2,400 to 3,000 m (7,874 to 9,843 ft), above which the snow is permanent and the temperatures hover around the freezing point even July and August. High-water levels in streams and rivers peak in June and July when the snow is still melting at the higher altitudes. Question: What areas experience periodic flooding from rapid snowmelt and runoff?

Answer:
The areas that are not arid and receive high precipitation