title: If column A equals column B then return value in column C
body: <p>I have a spreadsheet with different database cuts of data as it existed in a past stage and a current stage.</p>
  
  <p>I want to see if "Company A" in column A who was in the Negotiation stage in Column B now exists as "Company A" in column C (a subset of Column A) that is now in a Closed Won stage in column D.  If this is the case, I want to return a $ amount value in Column E.  </p>
  
  <p>Ignoring my specific scenario, the core logic I need is if column A equals column B then return the value in column C.</p>