user: Question: In which year did Blount County build a bridge in Cleveland that was listed on 1981-08-20?
Columns: ['Name', 'Built', 'Listed', 'Location', 'County']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Clarkson Bridge', '1904', '1974-06-25', 'Cullman', 'Cullman']
SQL:

assistant: SELECT "Built" FROM "Table" WHERE "County" = 'Blount' AND "Listed" = '1981-08-20' AND "Location" = 'Cleveland';