A = (-0.68, 2.78)
c = Circle(A, 5)
B = Point(c)
C = Point(c)
D = Point(c)
hulknurk1, d, b, c_1 = Polygon(B, C, D)
α = Angle(B, D, C)
β = Angle(D, C, B)
γ = Angle(C, B, D)