CREATE TABLE "table1_21696800_1" (
  "no" real,
  "num" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "u_s_air_date" text,
  "production_code" text,
  "u_s_viewers_million" text
);

Question: What's the number of the episode seen by 2.24 million people in the US?
SQL: SELECT "num" FROM "table1_21696800_1" WHERE "u_s_viewers_million"='2.24';

Question: How many millions of people in the US saw the episode titled "Rabid"?
SQL: SELECT "u_s_viewers_million" FROM "table1_21696800_1" WHERE "title"='\"Rabid\"';

Question: How many different episode numbers are there for episodes directed by Wayne Rose?
SQL: SELECT COUNT("num") FROM "table1_21696800_1" WHERE "directed_by"='Wayne Rose';

Question: How many millions of people in the US saw the episode titled "Kandor"?
SQL: SELECT "u_s_viewers_million" FROM "table1_21696800_1" WHERE "title"='\"Kandor\"';