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_15846 ( "Order Year" text, "Manufacturer" text, "Model" text, "Fleet Series (Quantity)" text, "Powertrain (Engine/Transmission)" text, "Fuel Propulsion" text )

### Question ###
what is the fuel propulsion where the fleet series (quantity) is 310-329 (20)?

### Accurate SQL ###

SELECT "Fuel Propulsion" FROM table_15846 WHERE "Fleet Series (Quantity)" = '310-329 (20)'