How many days after the Pátria arriving in Dili did the British steamship Aldenham arrive in Dili?
return the  Pátria arrives in  Dili ;return the  British steamship Aldenham arrives in  Dili ;return day of #1 ;return day of #2 ;return the  difference of #4 and  #3
['select', 'select', 'project', 'project', 'arithmetic']