Problem: Many contemporary uses of uranium exploit its unique nuclear properties. Uranium-235 has the distinction of being the only naturally occurring fissile isotope. Uranium-238 is fissionable by fast neutrons, and is fertile, meaning it can be transmuted to fissile plutonium-239 in a nuclear reactor. Another fissile isotope, uranium-233, can be produced from natural thorium and is also important in nuclear technology. While uranium-238 has a small probability for spontaneous fission or even induced fission with fast neutrons, uranium-235 and to a lesser degree uranium-233 have a much higher fission cross-section for slow neutrons. In sufficient concentration, these isotopes maintain a sustained nuclear chain reaction. This generates the heat in nuclear power reactors, and produces the fissile material for nuclear weapons. Depleted uranium (238U) is used in kinetic energy penetrators and armor plating.
Along with uranium-235, what isotope is noted for having a high fission cross-section for slow neutrons?
The answer is the following: uranium-233

Problem: In later editions of the book, Darwin traced evolutionary ideas as far back as Aristotle; the text he cites is a summary by Aristotle of the ideas of the earlier Greek philosopher Empedocles. Early Christian Church Fathers and Medieval European scholars interpreted the Genesis creation narrative allegorically rather than as a literal historical account; organisms were described by their mythological and heraldic significance as well as by their physical form. Nature was widely believed to be unstable and capricious, with monstrous births from union between species, and spontaneous generation of life.
What kind of births did the Christian Church fathers believe occurred in nature?
The answer is the following: monstrous births from union between species, and spontaneous generation of life.

Problem: Philadelphia's two major daily newspapers are The Philadelphia Inquirer, which is the eighteenth largest newspaper and third-oldest surviving daily newspaper in the country, and the Philadelphia Daily News. Both newspapers were purchased from The McClatchy Company (after buying out Knight Ridder) in 2006 by Philadelphia Media Holdings and operated by the group until the organization declared bankruptcy in 2010. After two years of financial struggle, the two newspapers were sold to Interstate General Media in 2012. The two newspapers have a combined circulation of about 500,000 readers.
Who owns the major papers in the city?
The answer is the following: Interstate General Media

Problem: Reflection of the original signal also occurs when it hits an extended conductive surface, in a fashion similar to a mirror. This effect can also be used to increase signal through the use of a reflector, normally placed behind the active element and spaced so the reflected signal reaches the element in-phase. Generally the reflector will remain highly reflective even if it is not solid; gaps less than 110 generally have little effect on the outcome. For this reason, reflectors often take the form of wire meshes or rows of passive elements, which makes them lighter and less subject to wind. The parabolic reflector is perhaps the best known example of a reflector-based antenna, which has an effective area far greater than the active element alone.
What effect would the use of a reflector have on a signal?
The answer is the following:
increase