CREATE TABLE table_31807 ("Class" TEXT, "Type" TEXT, "No. built  ( Converted* ) " TEXT, "Year built  ( Converted* ) " TEXT, "No. range" TEXT, "Withdrawn" FLOAT)

Tell me the year built for number built of 10
SELECT "Year built (Converted*)" FROM table_31807 WHERE "No. built (Converted*)" = '10'
SELECT "Year built (Converted*)" FROM "table_31807" WHERE "No. built (Converted*)" = '10'