CREATE TABLE "table1_17641206_4" (
  "episode" real,
  "original_title" text,
  "directed_by" text,
  "written_by" text,
  "original_airdate" text,
  "duration" text,
  "viewership" text
);

Question: What was the title of the episode with 5.04 million viewers?
SQL: SELECT "original_title" FROM "table1_17641206_4" WHERE "viewership"='5.04 million';

Question: What was the first airdate with a viewership of 4.77 million?
SQL: SELECT "original_airdate" FROM "table1_17641206_4" WHERE "viewership"='4.77 million';

Question: How many episodes  of 30 minutes were written by John Sullivan?
SQL: SELECT COUNT("duration") FROM "table1_17641206_4" WHERE "written_by"='John Sullivan';

Question: Who was the director when the writer was John Sullivan?
SQL: SELECT "directed_by" FROM "table1_17641206_4" WHERE "written_by"='John Sullivan';