text: SELECT sourceIP, totalRevenue, avgPageRank
  FROM
    (SELECT sourceIP,
            AVG(pageRank) as avgPageRank,
            SUM(adRevenue) as totalRevenue
      FROM Rankings AS R, UserVisits AS UV
      WHERE R.pageURL = UV.destURL
         AND UV.visitDate >= '1980-01-01' 
         AND UV.visitDate <= '1980-04-01' 
      GROUP BY UV.sourceIP) as T
    ORDER BY totalRevenue DESC LIMIT 1;
  