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.

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. 
Science

One protein that binds to this protein also binds to proline-rich sequences in the membrane proteins Vasp and Mena, and another is knocked out in the singed mutant. Phosphatidyl-inositol-4,5-bisphosphate regulates the binding of vinculin to both talin and this other protein, whose function is performed by nematode Major Sperm Protein in the only (*) eukaryotic cells known to lack one form of it. In addition to the aforementioned profilin and facsin, severin and gelsolin bind to this protein and sever it. Two toxins often used to study it are cytochalasins and phalloidin. Thymosin 4 sequesters this protein, which undergoes treadmilling because the critical concentration at its (+) and (-) ends is not the same. This protein consists of G monomers which polymerize into F filaments, which make up the microfilaments of the cytoskeleton. For 10 points, name this protein that forms cross-bridges with myosin in muscle cells.
Science

One section in this work claims that the application of mathematical methods to philosophy "will succeed in only building card-castles. " One chapter in this work refutes the cosmological and physio-theological arguments, and this work states that the title concept should regulate knowledge rather than constitute it in its first section. This work outlines the three ideas of the world, the thinker, and the being of all beings in one section and introduces the history, discipline, architectonic, and canon of the titular concept in "Transcendental Doctrines of Method. " Claiming to be the "New Copernican" revolution of philosophy, for 10 points, identify this investigation into synthetic a priori truths, a first of three metaphysical critiques by Immanuel Kant.

Social Science