Hello I need help on my physics If you could help on the three questions I Will appreciate it

I will mark brainliest!!

The variables for this experiment include mass, volume and the materials in the various balls, as well as their densities. in part iii, you will be investigating the questionable baseball. use the drop-down menus to complete the sentences and identify the independent and dependent variables. in part iii, the independent variable, the one that is intentionally manipulated, is . in part iii, the dependent variable, the one that you measure the response in, is

Elements that have one valence electron and are very reactive are called

Why is a noble gas different from other elements?