CREATE TABLE table_56115 ("Driver" TEXT, "Constructor" TEXT, "Laps" FLOAT, "Time/Retired" TEXT, "Grid" FLOAT)

Who constructed the car that has a Time/Retired of engine, and over 50 laps?
SELECT "Constructor" FROM table_56115 WHERE "Time/Retired" = 'engine' AND "Laps" > '50'
SELECT "Constructor" FROM "table_56115" WHERE "Laps" > '50' AND "Time/Retired" = 'engine'