CREATE TABLE "table1_23528223_2" (
  "no_in_series" real,
  "no_in_season" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text,
  "u_s_viewers_millions" text
);

Question: How many season numbers are there for the episode seen by 13.54 million people in the US?
SQL: SELECT COUNT("no_in_season") FROM "table1_23528223_2" WHERE "u_s_viewers_millions"='13.54';

Question: What's the series number of the episode directed by Skipp Sudduth?
SQL: SELECT "no_in_series" FROM "table1_23528223_2" WHERE "directed_by"='Skipp Sudduth';

Question: Who wrote the episode seen by 10.64 million people in the US?
SQL: SELECT "written_by" FROM "table1_23528223_2" WHERE "u_s_viewers_millions"='10.64';

Question: Who directed the episode titled "Redemptio"?
SQL: SELECT "directed_by" FROM "table1_23528223_2" WHERE "title"='\"Redemptio\"';