what is the least tonnage for the ship(s) that entered service on 11 february 1983?
CREATE TABLE table_name_21 (tonnage INTEGER, date_entered_service VARCHAR)
SELECT MIN(tonnage) FROM table_name_21 WHERE date_entered_service = "11 february 1983"
### Context: CREATE TABLE table_name_21 (tonnage INTEGER, date_entered_service VARCHAR) ### Question: what is the least tonnage for the ship(s) that entered service on 11 february 1983? ### Answer: SELECT MIN(tonnage) FROM table_name_21 WHERE date_entered_service = "11 february 1983"