Identify an advantage of using a fuel cell over a primary or secondary cell. I

Layers of rock containing fossils, like the layers illustrated here, are most likely composed of rocks.

Which of the following is not true about the atomic model of substances?

A2-kg bowling ball is 1 meter off the ground on a post when it falls. just before it reaches the ground,its traveling 4.4 m/s. assuming that there is no air resistant, which statement is true a. the initial potential energy is less then the final kinetic energy b. the mechanical energy is not conserved c. the mechanical energy is conserved d. the initial potential energy is greater than the final kinetic energy