Problem: Please answer a question about the following article about Uranium:
Uranium-235 was the first isotope that was found to be fissile. Other naturally occurring isotopes are fissionable, but not fissile. On bombardment with slow neutrons, its uranium-235 isotope will most of the time divide into two smaller nuclei, releasing nuclear binding energy and more neutrons. If too many of these neutrons are absorbed by other uranium-235 nuclei, a nuclear chain reaction occurs that results in a burst of heat or (in special circumstances) an explosion. In a nuclear reactor, such a chain reaction is slowed and controlled by a neutron poison, absorbing some of the free neutrons. Such neutron absorbent materials are often part of reactor control rods (see nuclear reactor physics for a description of this process of reactor control).
What is used to slow a chain reaction in a nuclear reactor?
A: neutron poison
Problem: Please answer a question about the following article about Hokkien:
In 677 (during the reign of Emperor Gaozong), Chen Zheng (陳政), together with his son Chen Yuanguang (陳元光), led a military expedition to pacify the rebellion in Fujian. They settled in Zhangzhou and brought the Middle Chinese phonology of northern China during the 7th century into Zhangzhou; In 885, (during the reign of Emperor Xizong of Tang), the two brothers Wang Chao (王潮) and Wang Shenzhi (王審知), led a military expedition force to pacify the Huang Chao rebellion. They brought the Middle Chinese phonology commonly spoken in Northern China into Zhangzhou. These two waves of migrations from the north generally brought the language of northern Middle Chinese into the Fujian region. This then gradually evolved into the Zhangzhou dialect.
What was responsible for bringing the language of North middle China to the Fujian region?
A: two waves of migrations from the north
Problem: Please answer a question about the following article about Financial crisis of 2007%E2%80%9308:
The U.S. Financial Crisis Inquiry Commission reported its findings in January 2011. It concluded that "the crisis was avoidable and was caused by: widespread failures in financial regulation, including the Federal Reserve’s failure to stem the tide of toxic mortgages; dramatic breakdowns in corporate governance including too many financial firms acting recklessly and taking on too much risk; an explosive mix of excessive borrowing and risk by households and Wall Street that put the financial system on a collision course with crisis; key policy makers ill prepared for the crisis, lacking a full understanding of the financial system they oversaw; and systemic breaches in accountability and ethics at all levels".
When did the U.S. Financial Crisis Inquiry Commission report its findings?
A: January 2011
Problem: Please answer a question about the following article about Sumer:
The Ubaid period is marked by a distinctive style of fine quality painted pottery which spread throughout Mesopotamia and the Persian Gulf. During this time, the first settlement in southern Mesopotamia was established at Eridu (Cuneiform: NUN.KI), c. 5300 BC, by farmers who brought with them the Hadji Muhammed culture, which first pioneered irrigation agriculture. It appears that this culture was derived from the Samarran culture from northern Mesopotamia. It is not known whether or not these were the actual Sumerians who are identified with the later Uruk culture. Eridu remained an important religious center when it was gradually surpassed in size by the nearby city of Uruk. The story of the passing of the me (gifts of civilization) to Inanna, goddess of Uruk and of love and war, by Enki, god of wisdom and chief god of Eridu, may reflect this shift in hegemony.
Where could the pottery be found spread throughout?
A:
Mesopotamia and the Persian Gulf