CREATE TABLE table_name_47 (power VARCHAR, fuel_system VARCHAR, displacement VARCHAR)

How much power does the fuel injection system have with a displacement of 1991cc?
SELECT power FROM table_name_47 WHERE fuel_system = "fuel injection" AND displacement = "1991cc"
SELECT "power" FROM "table_name_47" WHERE "1991cc" = "displacement" AND "fuel injection" = "fuel_system"