Problem: Mexico City:

Having been capital of a vast pre-Hispanic empire, and also the capital of richest viceroyalty within the Spanish Empire (ruling over a vast territory in the Americas and Spanish West Indies), and, finally, the capital of the United Mexican States, Mexico City has a rich history of artistic expression. Since the mesoamerican pre-Classical period the inhabitants of the settlements around Lake Texcoco produced many works of art and complex craftsmanship, some of which are today displayed at the world-renowned National Museum of Anthropology and the Templo Mayor museum. While many pieces of pottery and stone-engraving have survived, the great majority of the Amerindian iconography was destroyed during the Conquest of Mexico.

What are the main artifacts that have survived? 
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A: pottery and stone-engraving


Problem: Tajikistan:

The territory that now constitutes Tajikistan was previously home to several ancient cultures, including the city of Sarazm of the Neolithic and the Bronze Age, and was later home to kingdoms ruled by people of different faiths and cultures, including the Oxus civilization, Andronovo culture, Buddhism, Nestorian Christianity, Zoroastrianism, and Manichaeism. The area has been ruled by numerous empires and dynasties, including the Achaemenid Empire, Sassanian Empire, Hephthalite Empire, Samanid Empire, Mongol Empire, Timurid dynasty, and the Russian Empire. As a result of the breakup of the Soviet Union, Tajikistan became an independent nation in 1991. A civil war was fought almost immediately after independence, lasting from 1992 to 1997. Since the end of the war, newly established political stability and foreign aid have allowed the country's economy to grow.

The civil war lasted from 1982 to what year?
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A: unanswerable


Problem: Transistor:

The JEDEC EIA370 transistor device numbers usually start with "2N", indicating a three-terminal device (dual-gate field-effect transistors are four-terminal devices, so begin with 3N), then a 2, 3 or 4-digit sequential number with no significance as to device properties (although early devices with low numbers tend to be germanium). For example, 2N3055 is a silicon n–p–n power transistor, 2N1301 is a p–n–p germanium switching transistor. A letter suffix (such as "A") is sometimes used to indicate a newer variant, but rarely gain groupings.

What were most early devices made from?
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A: unanswerable


Problem: Antarctica:

Antarctica is the coldest of Earth's continents. The coldest natural temperature ever recorded on Earth was −89.2 °C (−128.6 °F) at the Soviet (now Russian) Vostok Station in Antarctica on 21 July 1983. For comparison, this is 10.7 °C (20 °F) colder than subliming dry ice at one atmosphere of partial pressure, but since CO2 only makes up 0.039% of air, temperatures of less than −150 °C (−238 °F) would be needed to produce dry ice snow in Antarctica. Antarctica is a frozen desert with little precipitation; the South Pole itself receives less than 10 cm (4 in) per year, on average. Temperatures reach a minimum of between −80 °C (−112 °F) and −89.2 °C (−128.6 °F) in the interior in winter and reach a maximum of between 5 °C (41 °F) and 15 °C (59 °F) near the coast in summer. Sunburn is often a health issue as the snow surface reflects almost all of the ultraviolet light falling on it. Given the latitude, long periods of constant darkness or constant sunlight create climates unfamiliar to human beings in much of the rest of the world.

What is the coldest temerature recorded in Russia?
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A:
unanswerable