Find the exact circumference of each circle using the given inscribed or circumscribed polygon.

Answer:
58π mi.
Step-by-step explanation:
The diameter of the circle = the hypotenuse of the right triangle ( by the angle subtended by a diameter theorem).
By Pythagoras:
diameter^2 = 40^2 + 42^2
= 3364
Diameter = 58 mi.
Now the circumference
= diameter * π
= 58π mi.