Because atoms are the small and can't be seen by your eyes. It is so small that scientists need to use a model. A model help scientists study things. So, scientists needs to study atoms using models.
The answer is 9. Calcium nitrate is made up
of 3 different elements that equal 9 atoms.
Answer:
375
Explanation:
325 + 50 = 375
just add them together and you get 375
