Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_94 (parameter VARCHAR, best_fit__wmap_only_ VARCHAR, symbol VARCHAR)

### Question ###
What is the parameter when the best fit (WMAP only) is .9 ± .1, and symbol is a?

### Accurate SQL ###

SELECT parameter FROM table_name_94 WHERE best_fit__wmap_only_ = ".9 ± .1" AND symbol = "a"