What is the goals against listed when the goals scored is 30?
CREATE TABLE "short_tournaments" (
  "year" text,
  "position" real,
  "games_played" real,
  "won" real,
  "tied" real,
  "lost" real,
  "goals_scored" real,
  "goals_against" real,
  "points" real,
  "postseason_place" text
);
SELECT "goals_against" FROM "short_tournaments" WHERE "goals_scored"=30;