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Cxample-2: A seawater sample was analyzed by ICP-AES for Cu. The sample was diluted by placing 10ml in a 100ml volumetric flask and adding 90ml of distilled water. A calibration plot was generated by diluting 1000 .ppm stock solution. 10ml of the stock solution were then placed in a 100ml volumetric flask and made up to the mark with distilled water. This solution was diluted in series as follow: Diluted sample =490 What is the conc. Of Cu in the original sea water sample