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: An approximation of it named for Russell uses the TDS value to determine one of its parameters via the Langelier approximation, while one constant that appears in it has units of moles per kilogram to the one half power, according the Bates-Guggenheim convention. Along with Guggenheim, Scatchard and Bronsted improved upon this model by developing the SIT theory, and that model has a better fit than a modification of it named for Davies. This relationship assumes the existence of only long-range interactions, and it was extended to account for Brownian motion by Lars Onsager. It assumes that the solvent is structure-less and that the solution is dilute, and the theory behind it implies that the electrostatic potential falls off exponentially when r is greater than the atomic radius due to screening by counter ions. For 10 points, identify this equation which is used to calculate the activity coefficients, and is named for a German and a Dutch scientist.

A: Science
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Q: This results from phonon interactions in simple metals. Joule heating is caused by this, while Wheatstone bridges are used to find unknown values for this quantity. The thermal form of this quantity is equal to the length of the material over the conductivity times the cross-sectional area. "Drug" this occurs when pathogens become able to survive exposure to certain drugs, rendering those drugs obsolete. Drag is sometimes called this of air. Name this term, the electrical type of which measures of the degree an object opposes the flow of an electrical current, measured in ohms.

A: Science
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Q: One of the most important holy sites for this group is the tomb of Nebi Shu'eib, or Jethro, and their other prophets include Sabalan and Al-Ya'afuri. They regard the calf as a symbol of negative forces, and call their theology hikma. Their secular juhal members are not granted access to holy books, a privilege reserved for the uqqal, and their emblem represents the 'superior ministers' as a five-colored star. Founded by Al-Hakim and based on seven central principles, FTP, identify this religious sect primarily concentrated in Israel, Lebanon, and Syria, an offshoot of Ismaili Islam whose members refer to themselves as muwahudeen.

A:
Social Science
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