Problem: Incandescent light bulb:

The first successful light bulb filaments were made of carbon (from carbonized paper or bamboo). Early carbon filaments had a negative temperature coefficient of resistance — as they got hotter, their electrical resistance decreased. This made the lamp sensitive to fluctuations in the power supply, since a small increase of voltage would cause the filament to heat up, reducing its resistance and causing it to draw even more power and heat even further. In the "flashing" process, carbon filaments were heated by current passing through them while in an evacuated vessel containing hydrocarbon vapor (usually gasoline). The carbon deposited on the filament by this treatment improved the uniformity and strength of filaments as well as their efficiency. A metallized or "graphitized" filament was first heated in a high-temperature oven before flashing and lamp assembly. This transformed the carbon into graphite which further strengthened and smoothed the filament. This also changed the filament to have a positive temperature coefficient, like a metallic conductor, and helped stabilize the lamp's power consumption, temperature and light output against minor variations in supply voltage.

What had a positive temperature coefficient of resistence?
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A: unanswerable


Problem: Frédéric Chopin:

Possibly the first venture into fictional treatments of Chopin's life was a fanciful operatic version of some of its events. Chopin was written by Giacomo Orefice and produced in Milan in 1901. All the music is derived from that of Chopin.

Where was the fictionalized "Chopin" produced?
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A: Milan


Problem: Estonia:

Estonia (i/ɛˈstoʊniə/; Estonian: Eesti [ˈeːsti]), officially the Republic of Estonia (Estonian: Eesti Vabariik), is a country in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia (343 km), and to the east by Lake Peipus and Russia (338.6 km). Across the Baltic Sea lies Sweden in the west and Finland in the north. The territory of Estonia consists of a mainland and 2,222 islands and islets in the Baltic Sea, covering 45,339 km2 (17,505 sq mi) of land, and is influenced by a humid continental climate.

What body of water borders Estonia on the west?
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A: the Baltic Sea


Problem: Armenia:

Although the Russian Caucasus Army of Imperial forces commanded by Nikolai Yudenich and Armenians in volunteer units and Armenian militia led by Andranik Ozanian and Tovmas Nazarbekian succeeded in gaining most of Ottoman Armenia during World War I, their gains were lost with the Bolshevik Revolution of 1917.[citation needed] At the time, Russian-controlled Eastern Armenia, Georgia, and Azerbaijan attempted to bond together in the Transcaucasian Democratic Federative Republic. This federation, however, lasted from only February to May 1918, when all three parties decided to dissolve it. As a result, the Dashnaktsutyun government of Eastern Armenia declared its independence on 28 May as the First Republic of Armenia under the leadership of Aram Manukian.

Who was the leader of the Armenian militia?
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A:
Andranik Ozanian