Table: race_results_96
Columns: year
entrant
chassis
engine
points

Question: What is the average year of an entrant that had fewer than 6 points and a Maserati Straight-6 engine?
SQL: SELECT AVG("year") FROM race_results_96 WHERE "points" < 6 AND "engine" = 'maserati straight-6'

Question: What entrant had a Maserati 250F chassis and fewer than 6 points before 1957?
SQL: SELECT "entrant" FROM race_results_96 WHERE "chassis" = 'maserati 250f' AND "year" < 1957 AND "points" < 6

Question: What chassis has a year of 1951?
SQL: SELECT "chassis" FROM race_results_96 WHERE "year" = 1951

Question: What is the chassis of Officine Alfieri Maserati with a Maserati Straight-6 engine and fewer than 6 points?
SQL: SELECT "chassis" FROM race_results_96 WHERE "engine" = 'maserati straight-6' AND "entrant" = 'officine alfieri maserati' AND "points" < 6