user: Question: What is Away Team Score, when Ground is Optus Oval, and when Away Team is Fremantle?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Ground', 'Date', 'Crowd']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'real']
Sample row: ['Fremantle', '8.9 (57)', 'Melbourne', '14.14 (98)', 'Subiaco Oval', 'Saturday, 17 February', 11392.0]
SQL:

assistant: SELECT "Away team score" FROM "Table" WHERE "Ground" = 'Optus Oval' AND "Away team" = 'Fremantle';