WHich Surface has an Opponent of gustavo kuerten?
CREATE TABLE table_name_13 (surface VARCHAR, opponent VARCHAR)
SELECT surface FROM table_name_13 WHERE opponent = "gustavo kuerten"
### Context: CREATE TABLE table_name_13 (surface VARCHAR, opponent VARCHAR) ### Question: WHich Surface has an Opponent of gustavo kuerten? ### Answer: SELECT surface FROM table_name_13 WHERE opponent = "gustavo kuerten"