How many more first downs did the Patriots have than the Packers?
return the  Patriots ;return the  Packers ;return first downs of #1 ;return first downs of #2 ;return number of  #3 ;return number of  #4 ;return the  difference of #5 and  #6
['select', 'select', 'project', 'project', 'aggregate', 'aggregate', 'arithmetic']