First of all, it is 2r

and it would be divide by 3.14 (pi) and then you should have the diameter. Then divide by 2 to find radius.
Answer:
¼ x 20 = 5
⅛ x 56 = 7
0.16 x 32 = 5.12
4.5 x 9.1 = 40.95
Step-by-step explanation:
Answer: ( A ) cleavage so the first one
Explanation: I hope this helps you