Which of the following statements about an apple falling from a tree is true? a) its kinetic energy decreases and its potential energy increases. b) its potential energy decreases and its kinetic energy increases. c) its kinetic and potential energies remain constant. d) its mechanical energy increases.

Scientists follow specific processes in order to determine valid explanations and conclusions from observations. david observed strange lights in the sky above his home outside of roswell, new mexico. the only explanation that makes sense to him is that there are ufos in the area. what should david do next to verify his explanation?