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The simplest method, used for small-scale production and often by hobbyists, is immersion etching, in which the board is submerged in etching solution such as ferric chloride. Compared with methods used for mass production, the etching time is long. Heat and agitation can be applied to the bath to speed the etching rate. In bubble etching, air is passed through the etchant bath to agitate the solution and speed up etching. Splash etching uses a motor-driven paddle to splash boards with etchant; the process has become commercially obsolete since it is not as fast as spray etching. In spray etching, the etchant solution is distributed over the boards by nozzles, and recirculated by pumps. Adjustment of the nozzle pattern, flow rate, temperature, and etchant composition gives predictable control of etching rates and high production rates.
What's the fastest and most easily controlled process for etching?
A: spray etching

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But although it meets the definition of outer space, the atmospheric density within the first few hundred kilometers above the Kármán line is still sufficient to produce significant drag on satellites. Most artificial satellites operate in this region called low Earth orbit and must fire their engines every few days to maintain orbit.[citation needed] The drag here is low enough that it could theoretically be overcome by radiation pressure on solar sails, a proposed propulsion system for interplanetary travel.[citation needed] Planets are too massive for their trajectories to be significantly affected by these forces, although their atmospheres are eroded by the solar winds.
What have satellite engines been suggested to be used for?
A: unanswerable

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Cognitive anthropology seeks to explain patterns of shared knowledge, cultural innovation, and transmission over time and space using the methods and theories of the cognitive sciences (especially experimental psychology and evolutionary biology) often through close collaboration with historians, ethnographers, archaeologists, linguists, musicologists and other specialists engaged in the description and interpretation of cultural forms. Cognitive anthropology is concerned with what people from different groups know and how that implicit knowledge changes the way people perceive and relate to the world around them.
Cognitive anthropologists want to know how the way people perceive and related to the world around them is linked to what?
A: implicit knowledge

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Sociologist James A. Beckford, in his 1975 study of Jehovah's Witnesses, classified the religion's organizational structure as Totalizing, characterized by an assertive leadership, specific and narrow objectives, control over competing demands on members' time and energy, and control over the quality of new members. Other characteristics of the classification include likelihood of friction with secular authorities, reluctance to co-operate with other religious organizations, a high rate of membership turnover, a low rate of doctrinal change, and strict uniformity of beliefs among members. Beckford identified the religion's chief characteristics as historicism (identifying historical events as relating to the outworking of God's purpose), absolutism (conviction that Jehovah's Witness leaders dispense absolute truth), activism (capacity to motivate members to perform missionary tasks), rationalism (conviction that Witness doctrines have a rational basis devoid of mystery), authoritarianism (rigid presentation of regulations without the opportunity for criticism) and world indifference (rejection of certain secular requirements and medical treatments).
What is the term for Jehovah's Witnesses' rejection of certain secular requirements and medical treatments?
A:
world indifference