Table: grand_prix_results_9
Columns: year
circuit
winning_drivers
winning_constructor
regulations
report

Question: What regulations have hudson as the winning constructor?
SQL: SELECT "regulations" FROM grand_prix_results_9 WHERE "winning_constructor" = 'hudson'

Question: What regulations have carlos arzani as the winning driver?
SQL: SELECT "regulations" FROM grand_prix_results_9 WHERE "winning_drivers" = 'carlos arzani'

Question: What is the latest year that has ferrari 166 fl as the winning constructor?
SQL: SELECT MAX("year") FROM grand_prix_results_9 WHERE "winning_constructor" = 'ferrari 166 fl'