Using a weight on a string called a plumb bob, it is possible to erect a pole that is exactly vertical, which means that the pole points directly toward the center of the earth. Two such poles are erected one hundred miles apart. If the the poles were extended they would meet at the center of the earth at an angle of . Compare the radius of the earth.
So that's the question and I'm just totally lost because I cant seem to picture it.
The equation for Arc length is