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 version of spectroscopy that is free of one form of this effect uses a standing wave to give radiation to a moving atom and is named for its two-photon transition. Due to this effect, atoms observe laser resonance leading to the phenomenon of optical molasses at its namesake cooling limit. Mossbauer spectroscopy uses this effect to modulate the energy of the incident gamma rays. An experiment that used a canal ray tube and a mirror to view light emissions was used to detect the transverse form of this effect, while its relativistic form involves changes equal to the square root of one plus beta over one minus beta. For 10 points, name this shift in the wavelength from a moving source that can be heard by an observer.

A: Science
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Q: It holds only when the molecular attraction between different components is equal to the attraction of any one component in its pure state. Dealing primarily with changes in colligative properties, it allows for the calculation of molecular weights of dissolved substances and leads to the definition of a solution as ideal. FTP, identify this law that relates the vapor pressure and mole fraction of a solution, a law named for its French discoverer.

A: Science
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Q: Takoka developed one version of this data structure called the 2-3 variety, while other versions of this structure include the skew and leftist varieties. Tarjans algorithm can be used to construct them in linear time, and Dijkstras algorithm often uses the Fibonacci type. This structures namesake sorting algorithm has a worst-case runtime of big O of n log n, and operations allowed within these structures include delete-max and merge. FTP, name these data structures used to implement priority queues, that consist of a tree in which each child node has a key less than that of the parent node.

A:
Science
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