O = Intersect(zAxis, yAxis)
a = Sphere(O, 5)
c = IntersectPath(xOyPlane, a)
Greenwich = Point(c)
C = Point(c)
P: (0, 0, 5)
E: (0, 0, -5)
d = Circle(P, Greenwich, E)
B = Point(c)
F: (0, 0, 4)
b = Plane(F, c)
e = IntersectPath(b, a)
f = Circle(P, C, E)
G, H = Intersect(e, f)
g = Segment(O, H)
h = Segment(O, C)
α = Angle(C, O, H)
i = Segment(P, O)
j = Segment(F, H)
I = Point(c)
k = Circle(P, I, E)
J, K = Intersect(e, k)
l = Segment(K, F)
p = CircleArc(F, K, H)
β = Angle(H, F, K)