What figure??? please show a photo or something so i can help
Answer:
The outer Ozone is helpful. Ozone occurs in two layers of the atmosphere. The layer closest to the earth's surface is called the troposphere; ground-level or (bad) ozone is an air pollutant that is harmful to breathe and it damages crops, trees and other vegetation. It is a main ingredient of urban smog.
Explanation:
This would be more of a chemistry question. Remember magnesium has a charge of 2+, and would need to hand off its two extra electrons. Fluorine can only take one electron at a time, so there needs to be two fluorines to take one magnesium's 2 electrons.
With lithium, it has a +1 charge, so it has one extra electron, which it can hand off to just 1 fluorine atom.
Another way of looking at this is:

+ 2

= MgF2 (the charges must balance out to zero)

+

= LiF (the charges balance out to zero)
That waves travel faster than the wave lenght!