Table: tv_episode_viewers_3
Columns: no_in_series
no_in_season
title
directed_by
written_by
original_air_date
u_s_viewers_millions

Question: What's the series number of the episode whose writer is David North?
SQL: SELECT MAX("no_in_series") FROM tv_episode_viewers_3 WHERE "written_by" = 'David North'

Question: What's the series number of the episode seen by 17.04 million people in the US?
SQL: SELECT MAX("no_in_series") FROM tv_episode_viewers_3 WHERE "u_s_viewers_millions" = '17.04'

Question: What's the title of the episode first seen by 18.15 million people in the US?
SQL: SELECT "title" FROM tv_episode_viewers_3 WHERE "u_s_viewers_millions" = '18.15'

Question: How many millions of people in the US saw the episode with series number 103?
SQL: SELECT "u_s_viewers_millions" FROM tv_episode_viewers_3 WHERE "no_in_series" = 103