user: Question: What is the average Week, when Opponent is Minnesota Vikings?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'September 5, 1993', 'Minnesota Vikings', 'W 24–7', '44,120']
SQL:

assistant: SELECT AVG("Week") FROM "Table" WHERE "Opponent" = 'Minnesota Vikings';