Task: Question Answering
Input (English): Passage: The Bears traveled to Philadelphia to take on the Eagles. The game was a defensive struggle throughout and a field goal fest through the first three quarters. Eagles kick David Akers connected on field goals of 24, 33, and 37. Bears kicker Robbie Gould hit on field goals of 31, 22, 41, and 45 respectively. The Bears held a three-point lead late until Eagles quarterback Donovan McNabb threw a touchdown strike to tight end Matt Schobel to give the Eagles a 16-12 lead. Eagles punter Sav Rocca pinned the Bears deep in their own territory with under two minutes remaining and no timeouts left, leaving the Bears to have to cover 97 yards if they wished to take the lead. Bears quarterback Brian Griese marched the team down the field and capped off the drive with a 15-yard touchdown pass to wide receiver Muhsin Muhammad with nine seconds remaining. The final was 19-16 Bears. The Eagles fell short on their final opportunity, and fell to 2-4. 
Question: How many yards longer was David Akers' longest field goal than his shortest? 
Answer type: Number 
Output (English): 13.