The circumference of a circle is equal to 72 pi. Find the radius of this circle.	Choose the most appropriate option
A) 35  B) 36  C) 37  D) 38  E) 39

Rationale: the circumference of a circle is given by c = 2 pi r , where r is the radius of the circle . substitute c by 72 pi to obtain the equation 72 pi = 2 pi r simplify and solve for r to obtain r = 36 answer b
Answer: B