CREATE TABLE table_name_29 (version VARCHAR, remixed_by VARCHAR, length VARCHAR)

What Version has a Remixed by Perky Park with a Length of 6:38?
SELECT version FROM table_name_29 WHERE remixed_by = "perky park" AND length = "6:38"
SELECT "version" FROM "table_name_29" WHERE "6:38" = "length" AND "perky park" = "remixed_by"