Problem: To be considered 'enriched', the uranium-235 fraction should be between 3% and 5%. This process produces huge quantities of uranium that is depleted of uranium-235 and with a correspondingly increased fraction of uranium-238, called depleted uranium or 'DU'. To be considered 'depleted', the uranium-235 isotope concentration should be no more than 0.3%. The price of uranium has risen since 2001, so enrichment tailings containing more than 0.35% uranium-235 are being considered for re-enrichment, driving the price of depleted uranium hexafluoride above $130 per kilogram in July 2007 from $5 in 2001.
How much did a pound of depleted uranium hexafluoride cost as of July 2007?
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Answer: unanswerable


Problem: In the UK, Italy and Australia which share the PAL A region, two versions of the NES were released; the "Mattel Version" and "NES Version". When the NES was first released in those countries, it was distributed by Mattel and Nintendo decided to use a lockout chip specific to those countries, different from the chip used in other European countries. When Nintendo took over European distribution in 1990, they produced consoles that were then labelled "NES Version"; therefore, the only differences between the two are the text on the front flap and texture on the top/bottom of the casing.
Which company didn't distribute the NES to the UK, Italy, and Australia?
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Answer: unanswerable


Problem: In 1918 Espanyol started a counter-petition against autonomy, which at that time had become a pertinent issue. Later on, an Espanyol supporter group would join the Falangists in the Spanish Civil War, siding with the fascists. Despite these differences in ideology, the derbi has always been more relevant to Espanyol supporters than Barcelona ones due to the difference in objectives. In recent years the rivalry has become less political, as Espanyol translated its official name and anthem from Spanish to Catalan.
When did Espanyol  offer a counter-petition against autonomy?
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Answer:
1918