CREATE TABLE table_55820 ("Class" TEXT, "Operator" TEXT, "Number" FLOAT, "Year Built" TEXT, "Cars per Set" FLOAT, "Unit Numbers." TEXT)

What unit has cars per set larger than 9 built in 1982?
SELECT "Unit Numbers." FROM table_55820 WHERE "Cars per Set" > '9' AND "Year Built" = '1982'
SELECT "Unit Numbers." FROM "table_55820" WHERE "Cars per Set" > '9' AND "Year Built" = '1982'