yogi_Apply Conditional Formatting To Highlight Second or Higher Instance Of A Name (duplicates) In A Column

                                         Google Spreadsheet   Post  #1647
Yogi Anand, D.Eng, P.E.      ANAND Enterprises LLC -- Rochester Hills MI     www.energyefficientbuild.com.   May-24-2014
post by Cinthis Gordillo: (https://productforums.google.com/forum/#!category-topic/docs/spreadsheets/0KcYllc3UaU)
I need to find duplicates in the same column
I need to know how to find duplicates in the same column with manually delete option. 

Please help

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