What kind of Crowd has a Ground of subiaco oval?
CREATE TABLE "group_b" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "ground" text,
  "crowd" real,
  "date" text
);
SELECT SUM("crowd") FROM "group_b" WHERE "ground"='subiaco oval';