CREATE TABLE table_7810 ("State" TEXT, "Preliminary Average" TEXT, "Interview" TEXT, "Swimsuit" TEXT, "Evening Gown" TEXT, "Semifinal Average" TEXT)

what is the preliminary average score when the interview score is 8.600 (6)?
SELECT "Preliminary Average" FROM table_7810 WHERE "Interview" = '8.600 (6)'
SELECT "Preliminary Average" FROM "table_7810" WHERE "Interview" = '8.600 (6)'