To know the Application version before upgrade and current version

If there is some oracle Aplication Instance say (11.5.10) got upgrade to R12. After upgarding the Instance/Application, If I want to know the older version. Then use the following select statement.

SELECT SUBSTR(snapshot_name,12,8)
FROM ad_snapshots
WHERE comments = 'Preseeded'
AND REPLACE(SUBSTR(snapshot_name,12,8),'.') =
(
SELECT max(to_number(replace(SUBSTR(snapshot_name,12,8),'.')))
FROM ad_snapshots
WHERE comments = 'Preseeded'
);

Use the following to know the current Oracle Apps Version.
---------------------------------------------------------------------

SELECT release_name FROM fnd_product_groups;