When the crowd was 8642 what was the away team's score?
CREATE TABLE "group_2" (
  "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_2" WHERE "crowd"=8642;