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Uranium-238 is the most stable isotope of uranium, with a half-life of about 4.468×109 years, roughly the age of the Earth. Uranium-235 has a half-life of about 7.13×108 years, and uranium-234 has a half-life of about 2.48×105 years. For natural uranium, about 49% of its alpha rays are emitted by each of 238U atom, and also 49% by 234U (since the latter is formed from the former) and about 2.0% of them by the 235U. When the Earth was young, probably about one-fifth of its uranium was uranium-235, but the percentage of 234U was probably much lower than this.
What fraction of the Earth's uranium was uranium-237 during the Earth's youth?
A: unanswerable

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In response to the 2007 United States Air Force nuclear weapons incident, Secretary of Defense Robert Gates accepted in June 2009 the resignations of Secretary of the Air Force Michael Wynne and the Chief of Staff of the Air Force General T. Michael Moseley. Moseley's successor, General Norton A. Schwartz, a former tactical airlift and special operations pilot was the first officer appointed to that position who did not have a background as a fighter or bomber pilot. The Washington Post reported in 2010 that General Schwartz began to dismantle the rigid class system of the USAF, particularly in the officer corps.
What US Secretary of Defense accepted resignations of top US Air Force officials in June of 2009?
A: Robert Gates

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Inns are buildings where travellers can seek lodging and, usually, food and drink. They are typically located in the country or along a highway. In Europe, they possibly first sprang up when the Romans built a system of roads two millennia ago.[citation needed] Some inns in Europe are several centuries old. In addition to providing for the needs of travellers, inns traditionally acted as community gathering places.
About how old are the oldest inns in Europe?
A: several centuries

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Allusions to legal issues in To Kill a Mockingbird, particularly in scenes outside of the courtroom, has drawn the attention from legal scholars. Claudia Durst Johnson writes that "a greater volume of critical readings has been amassed by two legal scholars in law journals than by all the literary scholars in literary journals". The opening quote by the 19th-century essayist Charles Lamb reads: "Lawyers, I suppose, were children once." Johnson notes that even in Scout and Jem's childhood world, compromises and treaties are struck with each other by spitting on one's palm and laws are discussed by Atticus and his children: is it right that Bob Ewell hunts and traps out of season? Many social codes are broken by people in symbolic courtrooms: Mr. Dolphus Raymond has been exiled by society for taking a black woman as his common-law wife and having interracial children; Mayella Ewell is beaten by her father in punishment for kissing Tom Robinson; by being turned into a non-person, Boo Radley receives a punishment far greater than any court could have given him. Scout repeatedly breaks codes and laws and reacts to her punishment for them. For example, she refuses to wear frilly clothes, saying that Aunt Alexandra's "fanatical" attempts to place her in them made her feel "a pink cotton penitentiary closing in on [her]". Johnson states, "[t]he novel is a study of how Jem and Scout begin to perceive the complexity of social codes and how the configuration of relationships dictated by or set off by those codes fails or nurtures the inhabitants of (their) small worlds."
Which character is chastised in the book for marrying a black woman?
A:
Dolphus Raymond