CREATE TABLE table_19529 ("No. in series" FLOAT, "Title" TEXT, "Directed by" TEXT, "Written by" TEXT, "Original air date" TEXT, "Production code" TEXT)

Which title had the production code 1ACX04?
SELECT "Title" FROM table_19529 WHERE "Production code" = '1ACX04'
SELECT "Title" FROM "table_19529" WHERE "Production code" = '1ACX04'