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Addition of lead(II) oxide lowers melting point, lowers viscosity of the melt, and increases refractive index. Lead oxide also facilitates solubility of other metal oxides and is used in colored glasses. The viscosity decrease of lead glass melt is very significant (roughly 100 times in comparison with soda glasses); this allows easier removal of bubbles and working at lower temperatures, hence its frequent use as an additive in vitreous enamels and glass solders. The high ionic radius of the Pb2+ ion renders it highly immobile in the matrix and hinders the movement of other ions; lead glasses therefore have high electrical resistance, about two orders of magnitude higher than soda-lime glass (108.5 vs 106.5 Ohm·cm, DC at 250 °C). For more details, see lead glass.
Lead oxide makes it easier to dissolve what?
A: other metal oxides

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On July 8, 2007 The Washington Post published excerpts from UCLA Professor Amy Zegart's book Spying Blind: The CIA, the FBI, and the Origins of 9/11. The Post reported from Zegart's book that government documents show the CIA and FBI missed 23 potential chances to disrupt the terrorist attacks of September 11, 2001. The primary reasons for the failures included: agency cultures resistant to change and new ideas; inappropriate incentives for promotion; and a lack of cooperation between the FBI, CIA and the rest of the United States Intelligence Community. The book blamed the FBI's decentralized structure, which prevented effective communication and cooperation among different FBI offices. The book suggested that the FBI has not evolved into an effective counter-terrorism or counter-intelligence agency, due in large part to deeply ingrained agency cultural resistance to change. For example, FBI personnel practices continue to treat all staff other than special agents as support staff, classifying intelligence analysts alongside the FBI's auto mechanics and janitors.
What facilitated communication among different FBI offices? 
A: unanswerable

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Overall, however, Whitehead's influence is very difficult to characterize. In English-speaking countries, his primary works are little-studied outside of Claremont and a select number of liberal graduate-level theology and philosophy programs. Outside of these circles his influence is relatively small and diffuse, and has tended to come chiefly through the work of his students and admirers rather than Whitehead himself. For instance, Whitehead was a teacher and long-time friend and collaborator of Bertrand Russell, and he also taught and supervised the dissertation of Willard Van Orman Quine, both of whom are important figures in analytic philosophy – the dominant strain of philosophy in English-speaking countries in the 20th century. Whitehead has also had high-profile admirers in the continental tradition, such as French post-structuralist philosopher Gilles Deleuze, who once dryly remarked of Whitehead that "he stands provisionally as the last great Anglo-American philosopher before Wittgenstein's disciples spread their misty confusion, sufficiency, and terror." French sociologist and anthropologist Bruno Latour even went so far as to call Whitehead "the greatest philosopher of the 20th century."
 Who are two of Whitehead's students that have not gone on to become renowned in the field of analytic philosophy?
A: unanswerable

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Between the 16th century and 19th century, the traditional Armenian homeland composed of Eastern Armenia and Western Armenia came under the rule of the Ottoman and successive Iranian empires, repeatedly ruled by either of the two over the centuries. By the 19th century, Eastern Armenia had been conquered by the Russian Empire, while most of the western parts of the traditional Armenian homeland remained under Ottoman rule. During World War I, Armenians living in their ancestral lands in the Ottoman Empire were systematically exterminated in the Armenian Genocide. In 1918, after the Russian Revolution, all non-Russian countries declared their independence from the Russian empire, leading to the establishment of the First Republic of Armenia. By 1920, the state was incorporated into the Transcaucasian Socialist Federative Soviet Republic, and in 1922 became a founding member of the Soviet Union. In 1936, the Transcaucasian state was dissolved, transforming its constituent states, including the Armenian Soviet Socialist Republic, into full Union republics. The modern Republic of Armenia became independent in 1991 during the dissolution of the Soviet Union.
When did Armenia gain its independence?
A:
1991