How many more residents were in Ungheni and Cahul than in Soroca and Orhei?
return Ungheni ;return Cahul ;return Soroca ;return Orhei ;return residents in  #1 ;return residents in  #2 ;return residents in  #3 ;return residents in  #4 ;return the  number of  #5 ;return the  number of  #6 ;return the  number of  #7 ;return the  number of  #8 ;return the  sum of #9 and  #10 ;return the  sum of #11 and  #12 ;return the  difference of #13 and  #14
['select', 'select', 'select', 'select', 'project', 'project', 'project', 'project', 'aggregate', 'aggregate', 'aggregate', 'aggregate', 'arithmetic', 'arithmetic', 'arithmetic']