You're the teach, I won't argue... Oh who am I kidding =), I had to check Wikipedia as I didn't learn the terminology in English:

Quadratic growth, 2 as the exponent, like prop cross section surface area: π*r*[SUP]2[/SUP]

Cubic growth, 3 as the exponent, like volume of sphere: 4π*r*[SUP]3[/SUP]/3

Exponential growth, the variable as the exponent, like bacteria growing: *a*[SUP]r[/SUP]

Sorry if I just argue against the language barrier here. And I don't claim to know the formulas for drag, power, efficiency, prop specs et c related to the surface area of an EDF.