CREATE TABLE "table1_18217753_1" (
  "series_num" real,
  "season_num" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text,
  "u_s_viewers_millions" text
);

Question: What is the original air date of season 9?
SQL: SELECT "original_air_date" FROM "table1_18217753_1" WHERE "season_num"=9;

Question: Who were the writers when there were 27.11 million viewers?
SQL: SELECT "written_by" FROM "table1_18217753_1" WHERE "u_s_viewers_millions"='27.11';

Question: How many series had viewers totaling 23.93 million?
SQL: SELECT COUNT("series_num") FROM "table1_18217753_1" WHERE "u_s_viewers_millions"='23.93';

Question: How many original air dates totaled 26.06 million viewers?
SQL: SELECT COUNT("original_air_date") FROM "table1_18217753_1" WHERE "u_s_viewers_millions"='26.06';