text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE table_2791668_1 (original_air_date VARCHAR, us_viewers__millions_ VARCHAR)
  ### Question:
  how many premieres had the episode that had 12.68 millions of north american viewers? 
  ### Answer:
  SELECT COUNT(original_air_date) FROM table_2791668_1 WHERE us_viewers__millions_ = "12.68"