Answer based on context:

Trying to break a two-game losing streak the Panthers flew to Raymond James Stadium for an NFC South rivalry match against the Buccaneers. In the 1st quarter the Panthers trailed early as QB Josh Freeman made an 8-yard TD pass to WR Arrelious Benn. They narrowed the lead with kicker John Kasay hitting a 46-yard field goal. They struggled further in the second quarter with RB LeGarrette Blount getting a 17-yard TD run; but they replied with RB Josh Vaughan making a 2-yard TD run. Tampa Bay scored again when Freeman found TE Kellen Winslow on a 20-yard TD pass. The Panthers tried to cut the lead down with Kasay's 28- and 48-yard field goals, but the Buccaneers pulled away in the fourth quarter with kicker Connor Barth nailing a 32-yard field goal, and with RB Cadillac Williams getting a 45-yard TD run.

How many yards difference exists between John Kasay longest and shortest field goal?
20