How many yards longer was Graham's total yards of field goals than Folk's total yards of field goals?
return Graham ;return field goals of #1 ;return yards  of #2 ;return sum of #3 ;return Folk ;return field goals of #5 ;return yards  of #6 ;return sum of #7 ;return difference of #4 and  #8
['select', 'project', 'project', 'aggregate', 'select', 'project', 'project', 'aggregate', 'arithmetic']