Problem: Eritrea:

During the last interglacial period, the Red Sea coast of Eritrea was occupied by early anatomically modern humans. It is believed that the area was on the route out of Africa that some scholars suggest was used by early humans to colonize the rest of the Old World. In 1999, the Eritrean Research Project Team composed of Eritrean, Canadian, American, Dutch and French scientists discovered a Paleolithic site with stone and obsidian tools dated to over 125,000 years old near the Bay of Zula south of Massawa, along the Red Sea littoral. The tools are believed to have been used by early humans to harvest marine resources like clams and oysters.

How old were the obsidian tools that were discovered by the Eritrean Research Project Team?
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A: over 125,000 years old

Problem: Late Middle Ages:

The Bulgarian Empire was in decline by the 14th century, and the ascendancy of Serbia was marked by the Serbian victory over the Bulgarians in the Battle of Velbazhd in 1330. By 1346, the Serbian king Stefan Dusan had been proclaimed emperor. Yet Serbian dominance was short-lived; the Serbian army led by the Lazar Hrebljevanovic was defeated by the Ottomans at the Battle of Kosovo in 1389, where most of the Serbian nobility was killed and the south of the country came under Ottoman occupation, as much of southern Bulgaria had become Ottoman territory in 1371. Northern remnants of Bulgaria were finally conquered by 1396, Serbia fell in 1459, Bosnia in 1463, and Albania was finally subordinated in 1479 only a few years after the death of Skanderbeg. Belgrade, an Hungarian domain at the time, was the last large Balkan city to fall under Ottoman rule, in 1521. By the end of the medieval period, the entire Balkan peninsula was annexed by, or became vassal to, the Ottomans.

In what year was the Battle of Kosovo?
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A: 1389

Problem: Mandolin:

The mandolin's popularity in the United States was spurred by the success of a group of touring young European musicians known as the Estudiantina Figaro, or in the United States, simply the "Spanish Students." The group landed in the U.S. on January 2, 1880 in New York City, and played in Boston and New York to wildly enthusiastic crowds. Ironically, this ensemble did not play mandolins but rather bandurrias, which are also small, double-strung instruments that resemble the mandolin. The success of the Figaro Spanish Students spawned other groups who imitated their musical style and costumes. An Italian musician, Carlo Curti, hastily started a musical ensemble after seeing the Figaro Spanish Students perform; his group of Italian born Americans called themselves the "Original Spanish Students," counting on the American public to not know the difference between the Spanish bandurrias and Italian mandolins. The imitators' use of mandolins helped to generate enormous public interest in an instrument previously relatively unknown in the United States.

What did the Origianl Spanish Students expect the American public not to know?
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A: the difference between the Spanish bandurrias and Italian mandolins

Problem: Avicenna:

Avicenna's astronomical writings had some influence on later writers, although in general his work could be considered less developed than Alhazen or Al-Biruni. One important feature of his writing is that he considers mathematical astronomy as a separate discipline to astrology. He criticized Aristotle's view of the stars receiving their light from the Sun, stating that the stars are self-luminous, and believed that the planets are also self-luminous. He claimed to have observed Venus as a spot on the Sun. This is possible, as there was a transit on May 24, 1032, but Avicenna did not give the date of his observation, and modern scholars have questioned whether he could have observed the transit from his location at that time; he may have mistaken a sunspot for Venus. He used his transit observation to help establish that Venus was, at least sometimes, below the Sun in Ptolemaic cosmology, i.e. the sphere of Venus comes before the sphere of the Sun when moving out from the Earth in the prevailing geocentric model.

What planet did Aristotle think was a spot on the moon?
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A:
unanswerable