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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Grey powder (chalk + mercury) is used in ?
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The correct answer is  Ans. is 'c' i.e., Dactylography A latent finger print may be developed by dusting the area with coloured powders to provide a contrast, and its pattern is recorded by photography. It can also be examined by oblique lighting. The commonly used powder is 'grey' powder (chalk and mercury), but white powders (lead carbonate or French chalk) are used for dusting dark surfaces.