Answer:
Circumference is 131.94
Explanation:
Circumference Formula is C=2πr
Enter 21 for r so it will look like C=2(π)(21)
That makes it equal 131.9468915 so since you are rounding to the nearest tenth, you go next to the 4 and since it is a 6, it will round the 4 up to a 5
so that will make the answer 131.94
Hope this helps!