Answer:
19.5
Step-by-step explanation:
Circumference is radius multiplied by 2, then multiplied by pi.
3.1 × 2= 6.2
6.2 × π= 19.477 ≈ 19.5
π also equals 3.14
radius r = 3.1 in
diameter d = 6.2 in
circumference C = 19.4778745 in
area A = 30.1907054 in2
