Table: tv_episode_data_48
Columns: no_in_series
no_in_season
title
directed_by
written_by
original_air_date
production_code
u_s_viewers_millions

Question: How many millions of people in the US watched the episode with season number 8?
SQL: SELECT "u_s_viewers_millions" FROM tv_episode_data_48 WHERE "no_in_season" = 8

Question: How many episodes had the series number of 38?
SQL: SELECT COUNT("directed_by") FROM tv_episode_data_48 WHERE "no_in_series" = 38

Question: How many different numbers of people in the US who'd seen the episode with a season number 8 are there?
SQL: SELECT COUNT("u_s_viewers_millions") FROM tv_episode_data_48 WHERE "no_in_season" = 8