How many yards of differential were there between Darren McFadden's rushing touchdown yards and his receiving touchdown yards?
return Darren McFadden ;return rushing touchdown of #1 ;return receiving touchdown of #1 ;return yards  of #2 ;return yards  of #3 ;return sum of #4 ;return sum of #4 ;return difference of #6 and  #7
['select', 'project', 'project', 'project', 'project', 'aggregate', 'aggregate', 'arithmetic']