Problem: As financial assets became more and more complex, and harder and harder to value, investors were reassured by the fact that both the international bond rating agencies and bank regulators, who came to rely on them, accepted as valid some complex mathematical models which theoretically showed the risks were much smaller than they actually proved to be. George Soros commented that "The super-boom got out of hand when the new products became so complicated that the authorities could no longer calculate the risks and started relying on the risk management methods of the banks themselves. Similarly, the rating agencies relied on the information provided by the originators of synthetic products. It was a shocking abdication of responsibility."
What happened to financial assets that made them harder to value?
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Answer: more complex


Problem: Alban Butler, writes on the subject: "Five months after this great Council, Nicae, St Alexander lying on his death-bed, recommended to his clergy and people the choice of Athanasius for his successor, thrice repeating his name. In consequence of his recommendation, the bishops of all Egypt assembled at Alexandria, and finding the people and clergy unanimous in their choice of Athanasius for patriarch, they confirmed the election about the middle of year 326. He seems, then, to have been about thirty years of age. " 
How old was Athanasius when he was chosen as Patriarch?
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Answer: thirty years


Problem: Energy sources unsuitable for mobile power plants, such as nuclear power, renewable hydroelectricity, or wind power can be used. According to widely accepted global energy reserve statistics, the reserves of liquid fuel are much less than gas and coal (at 42, 167 and 416 years respectively). Most countries with large rail networks do not have significant oil reserves and those that did, like the United States and Britain, have exhausted much of their reserves and have suffered declining oil output for decades. Therefore, there is also a strong economic incentive to substitute other fuels for oil. Rail electrification is often considered an important route towards consumption pattern reform. However, there are no reliable, peer-reviewed studies available to assist in rational public debate on this critical issue, although there are untranslated Soviet studies from the 1980s.
What is the recent incentive in  order to overcome oil scarcity?
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Answer:
to substitute other fuels