∡ AEC = (sđ AmC - sđ AnC)/2

O = (35.088428321678315, -0.056351981351984964)
B_1 = (37.55580011655011, -2.038339160839164)
c = Circle(O, B_1)
E = (42.429870629370626, 0.5706031468531431)
C_1 = Midpoint(E, O)
d = Circle(C_1, E)
A_1 = Midpoint(O, E)
e = Circle(A_1, E)
A = Intersect(c, e, 1.0)
C = Intersect(c, e, 2.0)
a = Ray(E, A)
b = Ray(E, C)
f = Segment(A, C)
n = CircleArc(O, C, A)
m = CircleArc(O, A, C)