CREATE TABLE "table1_16617011_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: Name the number air date for 14.20 us viewers
SQL: SELECT COUNT("original_air_date") FROM "table1_16617011_1" WHERE "u_s_viewers_millions"='14.20';

Question: Name the directed by for 15.15 viewers
SQL: SELECT "directed_by" FROM "table1_16617011_1" WHERE "u_s_viewers_millions"='15.15';