CREATE TABLE table_2959 ("Vehicle" TEXT, "Operating mode" TEXT, "EPA rated All-electric range" TEXT, "EPA rated combined fuel economy" TEXT, "Clean electric grid California  ( San Francisco ) " TEXT, "U.S. national average electric mix" TEXT, "Dirty electric grid Rocky Mountains  ( Denver ) " TEXT)

What is the epa rated combined fuel economy for the all-electric vehicle with dirty electric grid rocky mountains (denver) of 330 g/mi (205 g/km)?
SELECT "EPA rated combined fuel economy" FROM table_2959 WHERE "Operating mode" = 'All-electric' AND "Dirty electric grid Rocky Mountains (Denver)" = '330 g/mi (205 g/km)'
SELECT "EPA rated combined fuel economy" FROM "table_2959" WHERE "Dirty electric grid Rocky Mountains (Denver)" = '330 g/mi (205 g/km)' AND "Operating mode" = 'All-electric'