Change of Area =π (R+h)²-π(R)² = 2πRh+πh²

Change of Area per Foot =  2πR + πh 

As 'h' goes to zero, Rate of Change = 2πR

A_1 = Intersect(xAxis, yAxis)
B = Point(xAxis)
c = Circle(A_1, B)
A = Point(xAxis)
d = Circle(A_1, A)
C: (-(3.14) * x(B), 6.0)
D: (x(C) + 6.28 * x(B), y(C))
E: (-(3.14) * x(A), y(C) + x(A) - x(B))
F: (3.14 * x(A), y(C) + x(A) - x(B))
P, e, c_1, d_1, f = Polygon(E, C, D, F)
T2: "Change of Area =" + (3.14 * (x(A)^(2.0) - x(B)^(2.0)))
T3: "Change of Area per foot =" + (3.14 * (2.0 * x(B) + x(A) - x(B))) + " =  2π(" + (x(B) + (x(A) - x(B)) / 2.0) + ")"