CREATE TABLE table_1975 ("Number" TEXT, "Previous Number ( s ) " FLOAT, "Previous Class" TEXT, "Converted" FLOAT, "Use" TEXT, "Withdrawn" FLOAT, "Disposal" TEXT)

What is the smallest converted value at number 19?
SELECT MIN("Converted") FROM table_1975 WHERE "Number" = '19'
SELECT MIN("Converted") FROM "table_1975" WHERE "Number" = '19'