DOCSP-28205 fix storage cost description (#279)

Author: kanchana-mongodb

source/index.txt

@@ -92,8 +92,17 @@ Storage Costs
 following:
 
 - Cost per GB per day 
-- Cost for every one thousand storage access requests, where each 
-  access request is a dataset partition being processed
+- Cost for every one thousand storage access requests when querying
+  {+dl+} datasets using {+adf+}. Each access request corresponds to a
+  partition of data from a {+dl+} dataset that {+adf+} fetches to
+  process for a query. 
+
+  .. note:: 
+
+     You can now set limits on the amount of data that {+adf+} processes
+     for your queries to control costs. To learn more, see
+     :atlas:`Manage Atlas Data Federation Query Limits
+     </data-federation/query/manage-query-limits/>`. 
 
 To learn more, see the |service-pricing|.