In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.

Q: A weight of the nth power of this parameter is imputed to contributions to elements of an S matrix by nth-order Feynman diagrams; thus, this number can be considered the order of expansion in perturbative quantum electrodynamics. This constant is a measure of the electron anomalous magnetic moment, which explains its role in the relativistic splitting of atomic spectral lines that is its namesake. The coupling constant for the electromagnetic interactions of electrons, it is equal to the square of the ratio of the electron and Planck charges, or, in cgs units, the electron charge squared divided by the speed of light times Diracs constant. For ten points, name this physical constant usually denoted alpha and equal to about one over one hundred thirty-seven.

A: Science
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Q: Racial violence in this city began with the 1909 lynching of William James, as well as the later 1967 murder of black soldier Robert Hunt. Its Chief of Police was shot in 1969 violence stopped when Governor Richard Ogilvie sent in the National Guard. Rooster Cogburn opened a bar here after the Civil War, and it was the inspiration for Eden in Charles Dickens' Martin Chuzzlewit. Stephen Foster wrote a song about being "way down" in this city, which is where Magnolia Manor and Fort Defiance State Park are located. Huck and Jim intend to go to this city to obtain Jim's freedom in Huckleberry Finn, but they end up sailing past it. This city has the lowest elevation of any within Illinois and is located at the confluence of the Mississippi and Ohio Rivers. For 10 points, name this southernmost city in Illinois, which shares its name with a city in Egypt.

A: History
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Q: This element blocks the flow of calcium through NMDA channels, while compounds containing this metal are used to treat eclampsia. The hairpin ribozyme requires this metal to fold, and the the CorA protein transports this element across bacterial membranes. It is weakly bonded to the terminal phosphate groups of ATP. EDTA is used to chelate this metal, and it is found in a compound that contains a phytol side chain. Its stabilizing effect on the backbones of nucleic acids makes it a necessary cofactor for DNA polymerase, meaning its chloride is used in PCR reactions. Also found at the center of the porphyrin ring of chlorophyll, for 10 points, name this metal present as a +2 ion in solution, with atomic number 12 and symbol Mg.

A:
Science
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