What is the sum of Goals Against, when Lost is 45, and when Points is greater than 68?
CREATE TABLE "season_by_season_results" (
  "season" text,
  "games" real,
  "lost" real,
  "points" real,
  "pct_pct" real,
  "goals_for" real,
  "goals_against" real,
  "playoffs" text
);
SELECT SUM("goals_against") FROM "season_by_season_results" WHERE "lost"=45 AND "points">68;