CREATE TABLE table_15746 ("Year" FLOAT, "Denomination" TEXT, "Alloy" TEXT, "Reverse" TEXT, "Diameter" TEXT, "Weight" TEXT, "Obverse" TEXT, "Mintage" FLOAT, "Series" TEXT)

What is the denomination of the III Series?
SELECT "Denomination" FROM table_15746 WHERE "Series" = 'iii series'
SELECT "Denomination" FROM "table_15746" WHERE "Series" = 'iii series'