CREATE TABLE "table1_15938543_1" (
  "no_in_series" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "u_s_viewers_million" text,
  "original_air_date" text,
  "production_code" real
);

Question: Which series number had the production code of 116
SQL: SELECT "no_in_series" FROM "table1_15938543_1" WHERE "production_code"=116;

Question: Whats the title of the episode with production code 109
SQL: SELECT "title" FROM "table1_15938543_1" WHERE "production_code"=109;

Question: How many episodes were written by Jack Burditt & Robert Carlock
SQL: SELECT COUNT("production_code") FROM "table1_15938543_1" WHERE "written_by"='Jack Burditt & Robert Carlock';

Question: How many episodes had an original air date with 5.1 million viewers
SQL: SELECT COUNT("original_air_date") FROM "table1_15938543_1" WHERE "u_s_viewers_million"='5.1';

Question: Who wrote the episode that was directed by Dennie Gordon
SQL: SELECT "written_by" FROM "table1_15938543_1" WHERE "directed_by"='Dennie Gordon';