What is Away Team Score, when Ground is Optus Oval, and when Away Team is Fremantle?
CREATE TABLE "group_4" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "ground" text,
  "date" text,
  "crowd" real
);
SELECT "away_team_score" FROM "group_4" WHERE "ground"='optus oval' AND "away_team"='fremantle';