Hoping to take out their frustration from the previous week's performance, where they gave up a 17-point lead in the fourth quarter and lost to the Giants, the Eagles flew to the West Coast to take on the San Francisco 49ers.  The Eagles started off well with RB Brian Westbrook catching a 4-yard TD pass from QB Donovan McNabb, along with TE L.J. Smith catching a 1-yard TD pass.  In the second quarter, the 49ers would get on the board with kicker Joe Nedney kicking a 48-yard field goal, but the Eagles made sure to stay as far away as possible, with Brian Westbrook making a spectacular 71-yard TD run, along with kicker David Akers booting a 21-yard field goal.  In the third quarter, Philadelphia took advantage of a Niners miscue, as DT Mike Patterson returned a fumble 98 yards for a touchdown.  San Francisco would get a touchdown, ona a 1-yard run by rookie RB Noah Robinson.  In the fourth quarter,Noah Robinson would get another 1-yard TD run, but the Eagles managed to put the game away with Brian Westbrook getting an 8-yard TD run.  The 49ers would get one more TD, as QB Alex Smith completed a 15-yard pass to TE Eric Johnson, but fortunately, the Eagles would avenge last week's collapse with a win to give them the lead in the NFC East at 2-1.
Question: How many yards was the shortest field goal?
Answer: 21