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.

Q: Passage: During its formative period, the term madrasah referred to a higher education institution, whose curriculum initially included only the "religious sciences", whilst philosophy and the secular sciences were often excluded. The curriculum slowly began to diversify, with many later madaris teaching both the religious and the "secular sciences", such as logic, mathematics and philosophy. Some madaris further extended their curriculum to history, politics, ethics, music, metaphysics, medicine, astronomy and chemistry. The curriculum of a madrasah was usually set by its founder, but most generally taught both the religious sciences and the physical sciences. Madaris were established throughout the Islamic world, examples being the 9th century University of al-Qarawiyyin, the 10th century al-Azhar University (the most famous), the 11th century Niẓāmīyah, as well as 75 madaris in Cairo, 51 in Damascus and up to 44 in Aleppo between 1155 and 1260. Many more were also established in the Andalusian cities of Córdoba, Seville, Toledo, Granada (Madrasah of Granada), Murcia, Almería, Valencia and Cádiz during the Caliphate of Córdoba. Question: Who decided the content that would be delivered in a particular madrasah?

A: its founder
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Q: Passage: Naturally occurring glass, especially the volcanic glass obsidian, has been used by many Stone Age societies across the globe for the production of sharp cutting tools and, due to its limited source areas, was extensively traded. But in general, archaeological evidence suggests that the first true glass was made in coastal north Syria, Mesopotamia or ancient Egypt. The earliest known glass objects, of the mid third millennium BCE, were beads, perhaps initially created as accidental by-products of metal-working (slags) or during the production of faience, a pre-glass vitreous material made by a process similar to glazing. Question: What was obsidian used to make in prehistoric times?

A: cutting tools
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Q: Passage: On February 7, 1987, dozens of political prisoners were freed in the first group release since Khrushchev's "thaw" in the mid-1950s. On May 6, 1987, Pamyat, a Russian nationalist group, held an unsanctioned demonstration in Moscow. The authorities did not break up the demonstration and even kept traffic out of the demonstrators' way while they marched to an impromptu meeting with Boris Yeltsin, head of the Moscow Communist Party and at the time one of Gorbachev's closest allies. On July 25, 1987, 300 Crimean Tatars staged a noisy demonstration near the Kremlin Wall for several hours, calling for the right to return to their homeland, from which they were deported in 1944; police and soldiers merely looked on. Question: Prior to 1987 when was the last large release of prisoners?

A:
mid-1950s.
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