The Dallas Cowboys began their season at FedExField on Sunday night against their NFC East rival, the Washington Redskins.  The Cowboys trailed early in the first quarter as Redskins kicker Graham Gano got a 29-yard field goal.  Dallas would then trail in the second quarter as cornerback DeAngelo Hall returned a fumble 25 yards for a touchdown. In the third quarter, Dallas would finally get on the board as quarterback Tony Romo completed a 4-yard touchdown pass to wide receiver Miles Austin.  Washington would respond in the fourth quarter as Gano made a 49-yard field goal.  Afterwards, Romo threw what would have been the game-winning 13-yard touchdown pass to wide receiver Roy Williams, but a holding call on offensive tackle Alex Barron effectively ended the game.
Question: How many yards shorter was Graham Gano's first field goal than his last?
Answer: 20