Table: railway_stock_history
Columns: class
quantity
type
delivered
k_b_sts_b_class
retired

Question: What is the type of the locomotive which was delivered in 1857-59?
SQL: SELECT "type" FROM railway_stock_history WHERE "delivered" = '1857-59'

Question: What is the highest quantity of the b ix k.b.sts.b.?
SQL: SELECT MAX("quantity") FROM railway_stock_history WHERE "k_b_sts_b_class" = 'b ix'

Question: What is the lowest quantity of the 1b n2 type, which was retired in 1907-12?
SQL: SELECT MIN("quantity") FROM railway_stock_history WHERE "type" = '1b n2' AND "retired" = '1907-12'