Problem: Germans:

After Christianization, the Roman Catholic Church and local rulers led German expansion and settlement in areas inhabited by Slavs and Balts, known as Ostsiedlung. During the wars waged in the Baltic by the Catholic German Teutonic Knights; the lands inhabited by the ethnic group of the Old Prussians (the current reference to the people known then simply as the "Prussians"), were conquered by the Germans. The Old Prussians were an ethnic group related to the Latvian and Lithuanian Baltic peoples. The former German state of Prussia took its name from the Baltic Prussians, although it was led by Germans who had assimilated the Old Prussians; the old Prussian language was extinct by the 17th or early 18th century. The Slavic people of the Teutonic-controlled Baltic were assimilated into German culture and eventually there were many intermarriages of Slavic and German families, including amongst the Prussia's aristocracy known as the Junkers. Prussian military strategist Karl von Clausewitz is a famous German whose surname is of Slavic origin. Massive German settlement led to the assimilation of Baltic (Old Prussians) and Slavic (Wends) populations, who were exhausted by previous warfare.

Who was the Old Prussians ethnic group related to?
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A: Latvian and Lithuanian Baltic peoples

Problem: Windows 8:

Windows 8 was released to a mixed critical reception. Although reaction towards its performance improvements, security enhancements, and improved support for touchscreen devices was positive, the new user interface of the operating system was widely criticized for being potentially confusing and difficult to learn (especially when used with a keyboard and mouse instead of a touchscreen). Despite these shortcomings, 60 million Windows 8 licenses have been sold through January 2013, a number which included both upgrades and sales to OEMs for new PCs.

How many Windows 8 licenses were purchased by January 2012?
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A: unanswerable

Problem: Middle Ages:

In the 11th century, the Seljuk Turks took over much of the Middle East, occupying Persia during the 1040s, Armenia in the 1060s, and Jerusalem in 1070. In 1071, the Turkish army defeated the Byzantine army at the Battle of Manzikert and captured the Byzantine Emperor Romanus IV (r. 106871). The Turks were then free to invade Asia Minor, which dealt a dangerous blow to the Byzantine Empire by seizing a large part of its population and its economic heartland. Although the Byzantines regrouped and recovered somewhat, they never fully regained Asia Minor and were often on the defensive. The Turks also had difficulties, losing control of Jerusalem to the Fatimids of Egypt and suffering from a series of internal civil wars. The Byzantines also faced a revived Bulgaria, which in the late 12th and 13th centuries spread throughout the Balkans.

Who was taken prisoner at the Battle of Manzikert?
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A: Byzantine Emperor Romanus IV

Problem: Nigeria:

During the oil boom of the 1970s, Nigeria joined OPEC and the huge revenue generated made the economy richer. Despite huge revenues from oil production and sale, the military administration did little to improve the standard of living of the population, help small and medium businesses, or invest in infrastructure. As oil revenues fuelled the rise of federal subventions to states, the federal government became the centre of political struggle and the threshold of power in the country. As oil production and revenue rose, the Nigerian government became increasingly dependent on oil revenues and the international commodity markets for budgetary and economic concerns. It did not develop other sources of the economy for economic stability. That spelled doom to federalism in Nigeria.

Who failed to use the oil revenues to invest in infrastructure?
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A:
the military administration