How many days after the negotiating of the Anglo-Irish Treaty did the entire island of Ireland become the Irish Free State?
return the  negotiating of the   Anglo-Irish Treaty ;return the  entire island of Ireland become the   Irish Free State ;return day of #1 ;return day of #2 ;return the  difference of #4 and  #3
['select', 'select', 'project', 'project', 'arithmetic']