What was the original air date of the episode written by Michelle Offen?
CREATE TABLE "season_three_2011" (
  "series_num" real,
  "episode_num" real,
  "title" text,
  "written_by" text,
  "directed_by" text,
  "viewers" real,
  "original_airdate" text
);
SELECT "original_airdate" FROM "season_three_2011" WHERE "written_by"='Michelle Offen';