Table: race_results_64
Columns: year
entrant
chassis
engine
points

Question: How many years did Barclay Nordica Arrows BMW enter with Cosworth v8 engine?
SQL: SELECT SUM("year") FROM race_results_64 WHERE "entrant" = 'barclay nordica arrows bmw' AND "engine" = 'cosworth v8'

Question: How many years did barclay nordica arrows bmw enter with a bmw str-4 t/c engine with less than 1 point?
SQL: SELECT SUM("year") FROM race_results_64 WHERE "engine" = 'bmw str-4 t/c' AND "entrant" = 'barclay nordica arrows bmw' AND "points" < 1

Question: How many years was ensign n180b a Chassis with 4 points?
SQL: SELECT SUM("year") FROM race_results_64 WHERE "points" = 4 AND "chassis" = 'ensign n180b'