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Natural uranium consists of three major isotopes: uranium-238 (99.28% natural abundance), uranium-235 (0.71%), and uranium-234 (0.0054%). All three are radioactive, emitting alpha particles, with the exception that all three of these isotopes have small probabilities of undergoing spontaneous fission, rather than alpha emission. There are also five other trace isotopes: uranium-239, which is formed when 238U undergoes spontaneous fission, releasing neutrons that are captured by another 238U atom; uranium-237, which is formed when 238U captures a neutron but emits two more, which then decays to neptunium-237; uranium-233, which is formed in the decay chain of that neptunium-237; and finally, uranium-236 and -240, which appear in the decay chain of primordial plutonium-244. It is also expected that thorium-232 should be able to undergo double beta decay, which would produce uranium-232, but this has not yet been observed experimentally.

What is the natural abundance of uranium-235?
Answer: 0.71%
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Computers control functions at many utilities, including coordination of telecommunications, the power grid, nuclear power plants, and valve opening and closing in water and gas networks. The Internet is a potential attack vector for such machines if connected, but the Stuxnet worm demonstrated that even equipment controlled by computers not connected to the Internet can be vulnerable to physical damage caused by malicious commands sent to industrial equipment (in that case uranium enrichment centrifuges) which are infected via removable media. In 2014, the Computer Emergency Readiness Team, a division of the Department of Homeland Security, investigated 79 hacking incidents at energy companies.

What is a potential attack vector for utilities such as the power grid?
Answer: The Internet
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In 2008, the High Court in South Africa ruled that Chinese South Africans who were residents during the apartheid era (and their descendants) are to be reclassified as "Black people," solely for the purposes of accessing affirmative action benefits, because they were also "disadvantaged" by racial discrimination. Chinese people who arrived in the country after the end of apartheid do not qualify for such benefits.

Why was this classification made?
Answer:
solely for the purposes of accessing affirmative action benefits