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Nilanjan Bhowmick AIR 3, CSIR NET (Earth Science)
Suman Kumar
https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.toppr.com/ask/question/the-unit-cell-length-of-nacl-is-observed-to-be-05627-nm-by-xray-difference/&ved=2ahUKEwjOkZbtkevrAhUUyzgGHfTZCEwQFjAAegQICBAC&usg=AOvVaw1pjijgdD8hgAlHcHx8GBZn&cshid=1600172233735
see this similar question