Problem: Glass:

Most common glass contains other ingredients to change its properties. Lead glass or flint glass is more 'brilliant' because the increased refractive index causes noticeably more specular reflection and increased optical dispersion. Adding barium also increases the refractive index. Thorium oxide gives glass a high refractive index and low dispersion and was formerly used in producing high-quality lenses, but due to its radioactivity has been replaced by lanthanum oxide in modern eyeglasses.[citation needed] Iron can be incorporated into glass to absorb infrared energy, for example in heat absorbing filters for movie projectors, while cerium(IV) oxide can be used for glass that absorbs UV wavelengths.

What element is used in glass to help it from becoming more reflective?
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A: unanswerable


Problem: In July 2013, there were 41,000 non-Germans by citizenship living in Thuringia (1.9% of the population − among the smallest proportions of any state in Germany). Nevertheless, the number rose from 33,000 in July 2011, an increase of 24% in only two years. About 4% of the population are migrants (including persons that already received the German citizenship). The biggest groups of foreigners by citizenship are (as of 2012): Russians (3,100), Poles (3,000), Vietnamese (2,800), Turks (2,100) and Ukrainians (2,000). The amount of foreigners varies between regions: the college towns Erfurt, Jena, Weimar and Ilmenau have the highest rates, whereas there are almost no migrants living in the most rural smaller municipalities.
Which towns have the highest immigrant population?
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Answer: Erfurt, Jena, Weimar and Ilmenau


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
From the end of World War I until 1962, New Zealand controlled Samoa as a Class C Mandate under trusteeship through the League of Nations, then through the United Nations. There followed a series of New Zealand administrators who were responsible for two major incidents. In the first incident, approximately one fifth of the Samoan population died in the influenza epidemic of 1918–1919. Between 1919 and 1962, Samoa was administered by the Department of External Affairs, a government department which had been specially created to oversee New Zealand's Island Territories and Samoa. In 1943, this Department was renamed the Department of Island Territories after a separate Department of External Affairs was created to conduct New Zealand's foreign affairs.
What country was in control of Samoa up until 1962?
A: New Zealand


Context and question: In the 1960s, Downtown Houston consisted of a collection of mid-rise office structures. Downtown was on the threshold of an energy industry–led boom in 1970. A succession of skyscrapers were built throughout the 1970s—many by real estate developer Gerald D. Hines—culminating with Houston's tallest skyscraper, the 75-floor, 1,002-foot (305 m)-tall JPMorgan Chase Tower (formerly the Texas Commerce Tower), completed in 1982. It is the tallest structure in Texas, 15th tallest building in the United States, and the 85th tallest skyscraper in the world, based on highest architectural feature. In 1983, the 71-floor, 992-foot (302 m)-tall Wells Fargo Plaza (formerly Allied Bank Plaza) was completed, becoming the second-tallest building in Houston and Texas. Based on highest architectural feature, it is the 17th tallest in the United States and the 95th tallest in the world. In 2007, downtown Houston had over 43 million square feet (4,000,000 m²) of office space.
What was the original name of the JP Morgan Chase Tower?
Answer: Texas Commerce Tower


Question: The illuminated ceiling was once popular in the 1960s and 1970s but fell out of favor after the 1980s. This uses diffuser panels hung like a suspended ceiling below fluorescent lights, and is considered general lighting. Other forms include neon, which is not usually intended to illuminate anything else, but to actually be an artwork in itself. This would probably fall under accent lighting, though in a dark nightclub it could be considered general lighting.
Is there an answer to this question: What uses diffuser panels below fluorescent lights?

Answer: illuminated ceiling


Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Seeking national reconciliation between revolutionaries and Catholics, the Concordat of 1801 was signed on 15 July 1801 between Napoleon and Pope Pius VII. It solidified the Roman Catholic Church as the majority church of France and brought back most of its civil status. The hostility of devout Catholics against the state had now largely been resolved. It did not restore the vast church lands and endowments that had been seized during the revolution and sold off. As a part of the Concordat, he presented another set of laws called the Organic Articles.
Along with Napoleon, who signed the Concordat of 1801?
A:
Pope Pius VII