What source has a cardwell of 20%?
CREATE TABLE table_name_18 (source VARCHAR, cardwell VARCHAR)
SELECT source FROM table_name_18 WHERE cardwell = "20%"
### Context: CREATE TABLE table_name_18 (source VARCHAR, cardwell VARCHAR) ### Question: What source has a cardwell of 20%? ### Answer: SELECT source FROM table_name_18 WHERE cardwell = "20%"