Problem: In Babylonian astronomy, records of the motions of the stars, planets, and the moon are left on thousands of clay tablets created by scribes. Even today, astronomical periods identified by Mesopotamian proto-scientists are still widely used in Western calendars such as the solar year and the lunar month. Using these data they developed arithmetical methods to compute the changing length of daylight in the course of the year and to predict the appearances and disappearances of the Moon and planets and eclipses of the Sun and Moon. Only a few astronomers' names are known, such as that of Kidinnu, a Chaldean astronomer and mathematician. Kiddinu's value for the solar year is in use for today's calendars. Babylonian astronomy was "the first and highly successful attempt at giving a refined mathematical description of astronomical phenomena." According to the historian A. Aaboe, "all subsequent varieties of scientific astronomy, in the Hellenistic world, in India, in Islam, and in the West—if not indeed all subsequent endeavour in the exact sciences—depend upon Babylonian astronomy in decisive and fundamental ways."
Where can Kidinnu's solar year be found in use?
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Answer: today's calendars


Problem: A famous example of Arabic poetry and Persian poetry on romance (love) is Layla and Majnun, dating back to the Umayyad era in the 7th century. It is a tragic story of undying love much like the later Romeo and Juliet, which was itself said to have been inspired by a Latin version of Layla and Majnun to an extent. Ferdowsi's Shahnameh, the national epic of Iran, is a mythical and heroic retelling of Persian history. Amir Arsalan was also a popular mythical Persian story, which has influenced some modern works of fantasy fiction, such as The Heroic Legend of Arslan.
What ers dates to the 700's?
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Answer: unanswerable


Problem: The Chicago Transit Authority's elevated train running through Evanston is called the Purple Line, taking its name from Northwestern's school color. The Foster and Davis stations are within walking distance of the southern end of the campus, while the Noyes station is close to the northern end of the campus. The Central station is close to Ryan Field, Northwestern's football stadium. The Evanston Davis Street Metra station serves the Northwestern campus in downtown Evanston and the Evanston Central Street Metra station is near Ryan Field. Pace Suburban Bus Service and the CTA have several bus routes that run through or near the Evanston campus.
 Which train station is close to the southern end of campus?
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Answer:
unanswerable