CREATE TABLE table_15221 ("Team" CLOB, "Car ( s ) " CLOB, "Driver ( s ) " CLOB, "Primary Sponsor ( s ) " CLOB, "Owner ( s ) " CLOB, "Crew Chief" CLOB)

What crew chief has an owner name Jack Roush and driver Greg Biffle?
SELECT "Crew Chief" FROM table_15221 WHERE "Owner(s)" = 'jack roush' AND "Driver(s)" = 'greg biffle'
SELECT "Crew Chief" FROM "table_15221" WHERE "Driver(s)" = 'greg biffle' AND "Owner(s)" = 'jack roush'