How much was the prize money for  rwe-sporthalle, mülheim ?
CREATE TABLE "final_results" (
  "year" real,
  "champion_average_in_final" text,
  "legs" text,
  "runner_up_average_in_final" text,
  "sponsor" text,
  "prize_fund" text,
  "champion" text,
  "runner_up" text,
  "venue" text
);
SELECT "prize_fund" FROM "final_results" WHERE "venue"='RWE-Sporthalle, Mülheim';