The question pretty much explains it. Remember that pi is the ratio of the circumference to diameter and has the approximate value of 3.14159.... And you've been given a radius of 2.2. Since the diameter is twice the radius, that means that the diameter is 2.2*2 = 4.4, so the total circumference is 4.4 times pi. The value of 13.82 is the actual circumference, but remember the question "... in terms of pi" So the answer is 4.4
