Answer:
13.88 cm
Step-by-step explanation:
Formula of circumference: C=[tex]\pi[/tex]d
since radius is 2 times the diameter we have to multiply by 2
C=2[tex]\pi[/tex]r
Substitute 3.14 for [tex]\pi[/tex] and r for 2.1 cm
C=2*3.14*2.1
3.14 times 2 is 6.28
C=6.28*2.1
C=13.188 cm
