Thermosphere. In this layer, atoms and molecules escape into space and satellites orbit the earth.
Answer:
the answer you have marked is correct.
C is correct.
The answer is B. This is because Sodium has 1 valence electron and Fluorine has 7 valence electrons. All elements want 8 valence electrons so they may be stale, like the noble gases are. Hope this helps.
The number of electrons that can be held in the second orbit are 8