The answer to the question
P=18000000/6 zeros. not sure how to do rest
Common thing is that their outmost shell is completely filled with the electrons. They are inert gases.
Have about 5 beakers all with different temperatures of water. Put in a teaspoon of salt at a time and when it stops dissolving stop adding and record how much salt it took. It should be more salt as the temperature rises. The independent variable is the waters temperature. The dependent variable is how much salt is used. Make sure that there is the same amount of water in each beaker. Or else it won’t work.