The length of arc ab is 28.61 what is the circumference of the circle

The
the calculus of the circumference depends on what is the value of central angle, so we can take for  example 120° the value of the central angle.

since the length of arc ab is 28.61, and the central angle is 120°, we can find the circumference simply by using the following formula:

ARC = Radius x Angle, so Radius = ARC / Angle = 28 .61  / 120° = 0.23 unit

the circumference of a circle is C = 2 x radius x Pie

C = 2 x radius x Pie = 2 x 0.23 x 3.14 = 1.49 unit

500 dollars and its probably more than that