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: Due to the expansion of trade and its geographical proximity, Kiev became the most important trade centre and chief among the communes; therefore the leader of Kiev gained political "control" over the surrounding areas. This princedom emerged from a coalition of traditional patriarchic family communes banded together in an effort to increase the applicable workforce and expand the productivity of the land. This union developed the first major cities in the Rus' and was the first notable form of self-government. As these communes became larger, the emphasis was taken off the family holdings and placed on the territory that surrounded. This shift in ideology became known as the verv'. Question: How did the leader of Kiev gain political control?

Answer: Due to the expansion of trade


Question: Passage: The term "Enlightenment" emerged in English in the later part of the 19th century, with particular reference to French philosophy, as the equivalent of the French term 'Lumières' (used first by Dubos in 1733 and already well established by 1751). From Immanuel Kant's 1784 essay "Beantwortung der Frage: Was ist Aufklärung?" ("Answering the Question: What is Enlightenment?") the German term became 'Aufklärung' (aufklären = to illuminate; sich aufklären = to clear up). However, scholars have never agreed on a definition of the Enlightenment, or on its chronological or geographical extent. Terms like "les Lumières" (French), "illuminismo" (Italian), "ilustración" (Spanish) and "Aufklärung" (German) referred to partly overlapping movements. Not until the late nineteenth century did English scholars agree they were talking about "the Enlightenment." Question: In what century did the term Enlightenment emerge in English?

Answer: 19th


Question: Passage: The space-consuming analog video signal of a LaserDisc limited playback duration to 30 minutes (CAV) or 60 minutes (CLV) per side because of the hardware manufacturer's refusal to reduce line count for increased playtime. After one side was finished playing, a disc has to be flipped over in order to continue watching a movie, and some titles fill two or more discs. Many players, especially units built after the mid-1980s, can "flip" discs automatically by rotating the optical pickup to the other side of the disc, but this is accompanied by a pause in the movie during the side change. If the movie is longer than what could be stored on two sides of a single disc, manually swapping to a second disc is necessary at some point during the film. One exception to this rule is the Pioneer LD-W1, which features two disc platters. In addition, perfect still frames and random access to individual still frames is limited only to the more expensive CAV discs, which only had a playing time of approximately 30 minutes per side. In later years, Pioneer and other manufacturers overcame this limitation by incorporating a digital memory buffer, which "grabbed" a single frame from a CLV disc. Question: What must be reduced in order to allow LaserDisc playback time to increase?

Answer:
line count