user: Question: What was the highest week with 84,856 in attendance?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Game site', 'Record', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'September 4, 2003', 'New York Jets', 'W 16-13', 'FedEx Field', '1-0', '85,420']
SQL:

assistant: SELECT MAX("Week") FROM "Table" WHERE "Attendance" = '84,856';