Question: What year was class of Undine?
SQL: SELECT "Year made" FROM "2-1169552-2" WHERE "Class" = 'Undine';

Question: What was the quantity preserved for quantity made of 15?
SQL: SELECT "Quantity preserved" FROM "2-1169552-2" WHERE "Quantity made" = '15';

Question: Name the year for Hercules
SQL: SELECT "Year made" FROM "2-1169552-2" WHERE "Class" = 'Hercules';