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: In Eastern Europe, Byzantium revived its fortunes under Emperor Basil I (r. 867886) and his successors Leo VI (r. 886912) and Constantine VII (r. 913959), members of the Macedonian dynasty. Commerce revived and the emperors oversaw the extension of a uniform administration to all the provinces. The military was reorganised, which allowed the emperors John I (r. 969976) and Basil II (r. 9761025) to expand the frontiers of the empire on all fronts. The imperial court was the centre of a revival of classical learning, a process known as the Macedonian Renaissance. Writers such as John Geometres (fl. early 10th century) composed new hymns, poems, and other works. Missionary efforts by both eastern and western clergy resulted in the conversion of the Moravians, Bulgars, Bohemians, Poles, Magyars, and Slavic inhabitants of the Kievan Rus'. These conversions contributed to the founding of political states in the lands of those peoplesthe states of Moravia, Bulgaria, Bohemia, Poland, Hungary, and the Kievan Rus'. Bulgaria, which was founded around 680, at its height reached from Budapest to the Black Sea and from the Dnieper River in modern Ukraine to the Adriatic Sea. By 1018, the last Bulgarian nobles had surrendered to the Byzantine Empire. Question: During what century did John Geometres flourish?

A: 10th
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Q: Passage: Mass production of glass window panes in the early twentieth century caused a similar effect. In glass factories, molten glass was poured onto a large cooling table and allowed to spread. The resulting glass is thicker at the location of the pour, located at the center of the large sheet. These sheets were cut into smaller window panes with nonuniform thickness, typically with the location of the pour centered in one of the panes (known as "bull's-eyes") for decorative effect. Modern glass intended for windows is produced as float glass and is very uniform in thickness. Question: How was the bull's-eye used?

A: for decorative effect
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Q: Passage: Efforts have been made to protect Guam's coral reef habitats from pollution, eroded silt and overfishing, problems that have led to decreased fish populations. (Since Guam is a significant vacation spot for scuba divers, this is important.) In recent years, the Department of Agriculture, Division of Aquatic and Wildlife Resources has established several new marine preserves where fish populations are monitored by biologists. Before adopting U.S. Environmental Protection Agency standards, portions of Tumon Bay were dredged by the hotel chains to provide a better experience for hotel guests. Tumon Bay has since been made into a preserve. A federal Guam National Wildlife Refuge in northern Guam protects the decimated sea turtle population in addition to a small colony of Mariana fruit bats. Question: What has led to the decrease of fish near Guam?

A:
pollution, eroded silt and overfishing
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