Why are the element from period 2 grouped together

If forces acting on an object are unbalanced, which factors may result fron an unbalanced force? check all that apply

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?

Find the mass by adding the numbers from the three sliders