Respuesta :

Step-by-step explanation:

Circumference of Circle =

[tex]2\pi \: r[/tex]

given d = 19.4mi

r = 1/2d

= 1/2 x 19.4

= 9.7mi

Circumference of Circle =

[tex]2\pi(9.7) \\ = 19.4\pi \\ = 60.9mi \: (nearest \: tenth)[/tex]