There are two boxes on either side of a pulley. one weighs 7.5kg and falls 4.5m in 1.25s. find that box's acceleration and tension force, and the other box's mass.

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?