CREATE TABLE table_name_17 (engine VARCHAR, driver VARCHAR, tyre VARCHAR, constructor VARCHAR)

what is the engine when the tyre is d, the constructor is era and the driver is bob gerard?
SELECT engine FROM table_name_17 WHERE tyre = "d" AND constructor = "era" AND driver = "bob gerard"
SELECT "engine" FROM "table_name_17" WHERE "bob gerard" = "driver" AND "constructor" = "era" AND "d" = "tyre"