A = Point(xAxis)
B = Point(yAxis)
C = Point(xAxis)
f(x) = If[-2 ≤ x ≤ 2, sqrt(2.5^(2) - x^(2)) - 1.5]
c = CircumcircleArc(A, B, C)
d = Circle(A, B, C)
a = Surface(s, (f(s) * cos(t)), (f(s) * sin(t)), s, -2, 2, t, 0, (2 * π))