Scientists use siesmic waves also known as s-waves. These only go through solid layers not liquid. So when they reach a liquid level the wave shoots back and the scientists are able to determine what layers are solid and which are not.
Answer: energy=mgh 55*9.8*10.8= 5821.2 J <--- this can't be wrong, there's no other way to solve for it. set the potential energy equal to kinetic energy: 5821.2= 1/2...
