Table: filmography_6
Columns: title
series
director
production_num
release_date

Question: What release date has 6998 as the production num.?
SQL: SELECT "release_date" FROM filmography_6 WHERE "production_num" = '6998'

Question: What director has lt as the series, with 6982 as the production num.?
SQL: SELECT "director" FROM filmography_6 WHERE "series" = 'lt' AND "production_num" = '6982'

Question: What series has 1935-07-13 as the release date?
SQL: SELECT "series" FROM filmography_6 WHERE "release_date" = '1935-07-13'

Question: What title has lt as the series, ben hardaway as the director, with 6612 as the production num.?
SQL: SELECT "title" FROM filmography_6 WHERE "series" = 'lt' AND "director" = 'ben hardaway' AND "production_num" = '6612'