Problem: IBM:

On June 16, 1911, their four companies were consolidated in New York State by Charles Ranlett Flint to form the Computing-Tabulating-Recording Company (CTR). CTR's business office was in Endicott. The individual companies owned by CTR continued to operate using their established names until the businesses were integrated in 1933 and the holding company eliminated. The four companies had 1,300 employees and offices and plants in Endicott and Binghamton, New York; Dayton, Ohio; Detroit, Michigan; Washington, D.C.; and Toronto. They manufactured machinery for sale and lease, ranging from commercial scales and industrial time recorders, meat and cheese slicers, to tabulators and punched cards.

In what state was Endicott consolidated into one company?
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A: unanswerable


Problem: Sino-Tibetan relations during the Ming dynasty:

In 1207, the Mongol ruler Genghis Khan (r. 1206–1227) conquered and subjugated the ethnic Tangut state of the Western Xia (1038–1227). In the same year, he established diplomatic relations with Tibet by sending envoys there. The conquest of the Western Xia alarmed Tibetan rulers, who decided to pay tribute to the Mongols. However, when they ceased to pay tribute after Genghis Khan's death, his successor Ögedei Khan (r. 1229–1241) launched an invasion into Tibet.

Who invaded Tibet? 
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A: Ögedei Khan


Problem: Textual criticism:

Eclectic readings also normally give an impression of the number of witnesses to each available reading. Although a reading supported by the majority of witnesses is frequently preferred, this does not follow automatically. For example, a second edition of a Shakespeare play may include an addition alluding to an event known to have happened between the two editions. Although nearly all subsequent manuscripts may have included the addition, textual critics may reconstruct the original without the addition.

Why do people prefer a first edition Shakespeare play?
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A: unanswerable


Problem: Estonian language:

The two different historical Estonian languages (sometimes considered dialects), the North and South Estonian languages, are based on the ancestors of modern Estonians' migration into the territory of Estonia in at least two different waves, both groups speaking considerably different Finnic vernaculars. Modern standard Estonian has evolved on the basis of the dialects of Northern Estonia.

What was the minimum number of waves through which modern Estonians migrated into Estonia?
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A:
two