CREATE TABLE table_31964 ("Calls" TEXT, "Frequency" TEXT, "Branding" TEXT, "Format" TEXT, "Timeslot" TEXT, "Group owner" TEXT)

Tell me the format for calls of wrko
SELECT "Format" FROM table_31964 WHERE "Calls" = 'wrko'
SELECT "Format" FROM "table_31964" WHERE "Calls" = 'wrko'