• 2R = 2 1/2 x 3 1/2
  • 3R = 3 1/2 x 5
  • 4R = 4 x 6
  • 5R = 5 x 7
  • 6R = 6 x 8
  • 8R = 8 x 10
aug 7 2008 ∞
aug 17 2008 +