What is the name of the ship with pit props as Cargo sunk by u-48 *?
CREATE TABLE "merchant_ships" (
  "name" text,
  "flag" text,
  "cargo" text,
  "fate" text,
  "date_of_attack" text
);
SELECT "name" FROM "merchant_ships" WHERE "fate"='sunk by u-48 *' AND "cargo"='pit props';