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_38691 ( "Career Card" text, "Starting career/salary" text, "2nd career/salary" text, "3rd career/salary" text, "4th career/salary" text, "5th career/salary" text, "6th career/salary" text )

### Question ###
2nd career/salary of substitute teacher ($20,000) involves what 6th career/salary?

### Accurate SQL ###

SELECT "6th career/salary" FROM table_38691 WHERE "2nd career/salary" = 'substitute teacher ($20,000)'