CREATE TABLE table_55814 ("Locomotive" TEXT, "Serial No" TEXT, "Entered service" TEXT, "Gauge" TEXT, "Livery" TEXT)

What is the locomotive with a standard gauge and a serial number of 83-1015?
SELECT "Locomotive" FROM table_55814 WHERE "Gauge" = 'standard' AND "Serial No" = '83-1015'
SELECT "Locomotive" FROM "table_55814" WHERE "Gauge" = 'standard' AND "Serial No" = '83-1015'