Write a question about the following article: Coming off their win over the Giants, the Eagles stayed at home for a Week 9 Sunday night divisional duel with the Dallas Cowboys with the lead in the NFC East on the line. Philadelphia would trail in the first quarter as Cowboys running back Tashard Choice picked up a 2-yard touchdown run.  The Eagles would respond in the second quarter with a 45-yard and a 48-yard field goal from kicker David Akers, but Dallas would answer with kicker Nick Folk nailing a 22-yard field goal. In the third quarter, Philadelphia would take the lead as quarterback Donovan McNabb found tight end Brent Celek on an 11-yard touchdown pass.  However, the Cowboys struck back in the fourth quarter with Folk's 33-yard field goal and quarterback Tony Romo's 49-yard touchdown pass to wide receiver Miles Austin.  The Eagles tried to get a comeback, but could only muster up a 52-yard field goal from Akers.

Question about the article:
How many yards was the mean length for all field goals converted?