Respuesta :

Diameter= 2r= 7926.41

Now lets do the math

2r/2= 7926.41/2

r= 3963.205

Circumference= 2 x pi x r= 2 x 3.1415 x 3963.205= 24900.817 miles

Make sure you label! 
Circumference of a circle is: 2(pi)r

Since it's the diameter that is given, then 2r is just the diameter.

Circumference of the Earth = (7926.41 miles)(3.14159265358979...)

= 24901.55 miles