science
posted by Debra .
if the radius of a metal hoop that surrounds a silo were to expand by 1.00 m, the circumference of the hoop would increase by 6.28 m. If a metal hoop that completely surrounds the earth were to thermally expand so that its radius increased by 1.00m , by how much would its circumference increase?

Circumference = 2 pi R
(Change in circumference) = 2 pi *(change in R),
The answer is 2 pi = 6.28 m in both cases