Question: What circuit did Clay Regazzoni win?
SQL: SELECT "Circuit" FROM "1-1140090-6" WHERE "Winning driver" = 'Clay Regazzoni';

Question: What was the date when Chris Amon won?
SQL: SELECT "Date" FROM "1-1140090-6" WHERE "Winning driver" = 'Chris Amon';

Question: What circuit is the VI Rhein-Pokalrennen race in?
SQL: SELECT "Circuit" FROM "1-1140090-6" WHERE "Race Name" = 'VI Rhein-Pokalrennen';