What opponent has a week less than 16, with September 7, 2008 as the date?
CREATE TABLE "regular_season" (
  "week" real,
  "date" text,
  "time_pt" text,
  "opponent" text,
  "result" text,
  "record" text,
  "game_site" text
);
SELECT "opponent" FROM "regular_season" WHERE "week"<16 AND "date"='september 7, 2008';