Hi, I'm taking AP calculus in high school and I am completely baffled on this one..
Suppose you have a straight and level 1-mile long railroad track. Imagine that one end of the track is fastened to the ground and the rest of it is not fastened. King Kong walks by the unattached end and pushes it exactly 1 inch towards the fastened end so that the track bows up in a circular arc. How high is the track above the ground in the middle of the circular arc?
So, the track is basically in an arc since King Kong pushed it an inch inward.