Answer:
125.6
282.6
Step-by-step explanation:
How you find the circumference is easy.
The formula is 2πr, meaning you multiply 2 times pi (3.14) times the radius (20 m)
2 x 3.14 =
6.28 x 20 =
Circumference: 125.6
The second problem is easier than the last.
Instead of multiplying by 2, you'll only multiply 3.14 (pi) times 90.
3.14 x 90 =
Circumference: 282.6
