Table: ship_sms
Columns: date
ship
type
nationality
tonnage_grt

Question: what is the nationality of the ship appam?
SQL: SELECT "nationality" FROM ship_sms WHERE "ship" = 'appam'

Question: what is the tonnage grt of the ship author?
SQL: SELECT "tonnage_grt" FROM ship_sms WHERE "ship" = 'author'

Question: what is the most tonnage grt of any ship sunk or captured on 16 jan 16?
SQL: SELECT MAX("tonnage_grt") FROM ship_sms WHERE "date" = '16 jan 16'

Question: what is the total tonnage grt of the cargo ship(s) sunk or captured on 4 feb 16?
SQL: SELECT COUNT("tonnage_grt") FROM ship_sms WHERE "type" = 'cargo ship' AND "date" = '4 feb 16'