A cylinder at left with balls evenly spaced throughout the cylinder with an arrow leading to a cylinder at right with balls stacked near the bottom of the cylinder. Which change of state is shown in the model?

condensation
deposition
boiling
freezing

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?