Which PF per game has a Rank of 5?
CREATE TABLE "2009_nbl_ladder_championship_round" (
  "rank" real,
  "team" text,
  "played" real,
  "loss" real,
  "last_5" text,
  "streak" text,
  "pf_per_game" real,
  "pa_per_game" real,
  "pd_per_game" real,
  "winning_pct" text
);
SELECT MIN("pf_per_game") FROM "2009_nbl_ladder_championship_round" WHERE "rank"=5;