CREATE TABLE "u_s_nielsen_ratings" (
  "episode" real,
  "first_air_date" text,
  "rating_18_49" text,
  "share_18_49" real,
  "viewers_millions" text,
  "rank_timeslot" text,
  "rank_night" text
);

Question: How many records for number of viewers is listed for episode number 8? 
SQL: SELECT COUNT("viewers_millions") FROM "u_s_nielsen_ratings" WHERE "episode"=8;

Question: What was the 18 to 49 rating when 9.50 million watched?
SQL: SELECT "rating_18_49" FROM "u_s_nielsen_ratings" WHERE "viewers_millions"='9.50';

Question: what episode number had 11.73 million viewers? 
SQL: SELECT "episode" FROM "u_s_nielsen_ratings" WHERE "viewers_millions"='11.73';

Question: How many episodes had 11.47 million viewers? 
SQL: SELECT COUNT("episode") FROM "u_s_nielsen_ratings" WHERE "viewers_millions"='11.47';