user: ### NOW ANSWER:
Question: Which rebound was 8 and has and ast that was less than 57?
Columns: ['Nationality', 'No [a ]', 'Pos [a ]', 'From', 'School/club', 'Pts [b ]', 'Reb [b ]', 'Ast [b ]']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'real', 'real']
Sample row: ['United States', '4', 'F', '2013 2013', 'Connecticut', 209.0, 196.0, 36.0]
SQL:

assistant: SELECT AVG("Reb [b ]") FROM "Table" WHERE "No [a ]" = '8' AND "Ast [b ]" < 57.0;