by Leopold Plumtree » Fri Mar 16, 2007 8:56 am
The question's difficult to understand. Do you mean the surface area of a 60 gallon volume? What shape is this volume? Different shapes have different surface area to volume ratios.
A sphere displacing 60 US gallons will have slightly less area than 20 ft² (19.38 ft²), but I haven't seen many bags like that.