What is the away team's score of the game where the away team is Geelong?
CREATE TABLE "round_15" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "venue" text,
  "date" text
);
SELECT "away_team_score" FROM "round_15" WHERE "away_team"='geelong';