what is the tonnage grt of the ship author?
CREATE TABLE table_name_40 (tonnage_grt VARCHAR, ship VARCHAR)
SELECT tonnage_grt FROM table_name_40 WHERE ship = "author"
### Context: CREATE TABLE table_name_40 (tonnage_grt VARCHAR, ship VARCHAR) ### Question: what is the tonnage grt of the ship author? ### Answer: SELECT tonnage_grt FROM table_name_40 WHERE ship = "author"