Find the circumference of a circle whose area is 60pi cm^2.
a.

b.

c.

d.

  none of the offered choices is correct

Step-by-step explanation:

We can use the area equation to find the radius of the circle, then use that to find the circumference.

  A = πr²

  60π = πr²

  60 = r² . . . . . . . divide by π

  √60 = 2√15 = r . . . . take the square root

Now, the circumference is given by ...

  C = 2πr

  C = 2π(2√15) = 4π√15 . . . . cm

_____

If the area were 60 cm², answer choice B would be correct. Since it is 60π cm², no answer choice is correct.

4

step-by-step explanation: