Table: chelsea_0405_games
Columns: date
opponent
venue
result
attendance

Question: What is the average Attendance at Venue A on 16 October 2004?
SQL: SELECT AVG("attendance") FROM chelsea_0405_games WHERE "venue" = 'a' AND "date" = '16 october 2004'

Question: What is the lowest Attendance when Middlesbrough played at Venue A?
SQL: SELECT MIN("attendance") FROM chelsea_0405_games WHERE "opponent" = 'middlesbrough' AND "venue" = 'a'