CREATE TABLE table_20425 ("Issuing network" TEXT, "IIN ranges" TEXT, "Active" TEXT, "Length" TEXT, "Validation" TEXT)

What is the length for iin range 51-55?
SELECT "Length" FROM table_20425 WHERE "IIN ranges" = '51-55'
SELECT "Length" FROM "table_20425" WHERE "IIN ranges" = '51-55'