Question

Find the exact circumference of a circle with the given radius.

3½ cm

C =

A.7.5 cm
B.7 cm
C.6.25 cm

Answer 1

I don't see an answer choice for this question. The equation for circumference is 2$\pi$r
You should get 2pi(3.5)=21.99 

Answer 2

None of the answers are "exact" if you use 3.14 for pi.

That 3.14 is an approx. to pi.

If you want an exact answer, include "pi" in your answer, not a numerical value:

C = 2pi*r becomes     C = 2pi(3.5 cm) = 7pi cm, or 7$\pi$ cm