user: ### NOW ANSWER:
Question: what is the diameter (km) of feature of latitude 40.5S
Columns: ['Name', 'Latitude', 'Longitude', 'Diameter (km)', 'Year named', 'Name origin']
Types: ['text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Aibarchin Planitia', '73.0S', '25.0E', '1,200.0', 1997.0, 'Uzbek "Alpamysh" epic tale heroine.']
SQL:

assistant: SELECT "Diameter (km)" FROM "Table" WHERE "Latitude" = '40.5S';