CREATE TABLE table_79649 ("Class" TEXT, "Wheel arrangement" TEXT, "Fleet number ( s ) " TEXT, "Manufacturer" TEXT, "Serial numbers" TEXT, "Year made" TEXT, "Quantity made" TEXT, "Quantity preserved" TEXT)

what is the quantity made when the class is d-2?
SELECT "Quantity made" FROM table_79649 WHERE "Class" = 'd-2'
SELECT "Quantity made" FROM "table_79649" WHERE "Class" = 'd-2'