Problem: Russian Soviet Federative Socialist Republic:

For most of the Soviet Union's existence, it was commonly referred to as "Russia," even though technically "Russia" was only one republic within the larger union—albeit by far the largest, most powerful and most highly developed.

Which republic was the least developed?
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A: unanswerable


Problem: Iranian scientists outside Iran have also made some major contributions to science. In 1960, Ali Javan co-invented the first gas laser, and fuzzy set theory was introduced by Lotfi Zadeh. Iranian cardiologist, Tofy Mussivand invented and developed the first artificial cardiac pump, the precursor of the artificial heart. Furthering research and treatment of diabetes, HbA1c was discovered by Samuel Rahbar. Iranian physics is especially strong in string theory, with many papers being published in Iran. Iranian-American string theorist Kamran Vafa proposed the Vafa-Witten theorem together with Edward Witten. In August 2014, Maryam Mirzakhani became the first-ever woman, as well as the first-ever Iranian, to receive the Fields Medal, the highest prize in mathematics.
When did Ali Javan, an Iranian scientist, co-invent the first gas laser?
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Answer: 1960


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The halogen lamp reduces uneven evaporation of the filament and eliminates darkening of the envelope by filling the lamp with a halogen gas at low pressure, rather than an inert gas. The halogen cycle increases the lifetime of the bulb and prevents its darkening by redepositing tungsten from the inside of the bulb back onto the filament. The halogen lamp can operate its filament at a higher temperature than a standard gas filled lamp of similar power without loss of operating life. Such bulbs are much smaller than normal incandescent bulbs, and are widely used where intense illumination is needed in a limited space. Fiber-optic lamps for optical microscopy is one typical application.
How does the halogen bulb increase darkening over time?
A: unanswerable


Context and question: Marvel first licensed two prose novels to Bantam Books, who printed The Avengers Battle the Earth Wrecker by Otto Binder (1967) and Captain America: The Great Gold Steal by Ted White (1968). Various publishers took up the licenses from 1978 to 2002. Also, with the various licensed films being released beginning in 1997, various publishers put out movie novelizations. In 2003, following publication of the prose young adult novel Mary Jane, starring Mary Jane Watson from the Spider-Man mythos, Marvel announced the formation of the publishing imprint Marvel Press. However, Marvel moved back to licensing with Pocket Books from 2005 to 2008. With few books issued under the imprint, Marvel and Disney Books Group relaunched Marvel Press in 2011 with the Marvel Origin Storybooks line.
When did Marvel switch to the Disney Books Group?
Answer: unanswerable


Question: Migration plays an important role in Thuringia. The internal migration shows a strong tendency from rural areas towards the big cities. From 2008 to 2012, there was a net migration from Thuringia to Erfurt of +6,700 persons (33 per 1000 inhabitants), +1,800 to Gera (19 per 1000), +1,400 to Jena (14 per 1000), +1,400 to Eisenach (33 per 1000) and +1,300 to Weimar (21 per 1000). Between Thuringia and the other German states, the balance is negative: In 2012, Thuringia lost 6,500 persons to other federal states, the most to Bavaria, Saxony, Hesse and Berlin. Only with Saxony-Anhalt and Brandenburg the balance is positive. The international migration is fluctuating heavily. In 2009, the balance was +700, in 2010 +1,800, in 2011 +2,700 and in 2012 +4,800. The most important countries of origin of the Thuringia migrants from 2008 to 2012 were Poland (+1,700), Romania (+1,200), Afghanistan (+1,100) and Serbia/Montenegro/Kosovo (+1,000), whereas the balance was negative with Switzerland (−2,800) and Austria (−900).
Is there an answer to this question: How many migrants went to Eisenach? 

Answer: +1,400


Problem: Elizabeth II:

According to Paul Martin, Sr., by the end of the 1970s the Queen was worried that the Crown "had little meaning for" Pierre Trudeau, the Canadian Prime Minister. Tony Benn said that the Queen found Trudeau "rather disappointing". Trudeau's supposed republicanism seemed to be confirmed by his antics, such as sliding down banisters at Buckingham Palace and pirouetting behind the Queen's back in 1977, and the removal of various Canadian royal symbols during his term of office. In 1980, Canadian politicians sent to London to discuss the patriation of the Canadian constitution found the Queen "better informed ... than any of the British politicians or bureaucrats". She was particularly interested after the failure of Bill C-60, which would have affected her role as head of state. Patriation removed the role of the British parliament from the Canadian constitution, but the monarchy was retained. Trudeau said in his memoirs that the Queen favoured his attempt to reform the constitution and that he was impressed by "the grace she displayed in public" and "the wisdom she showed in private".

In what year did Pierre Trudeau become the Canadian prime minister?
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A:
unanswerable