How many were the viewers (in millions) of the series no. 45?
CREATE TABLE "table1_27847088_1" (
  "episode_no" real,
  "series_no" real,
  "episode" text,
  "director" text,
  "writer_s" text,
  "original_airdate" text,
  "viewers_millions" text
);
SELECT "viewers_millions" FROM "table1_27847088_1" WHERE "series_no"=45;