Answer:
I believe it's the lowest portion of the atmosphere
Uhh add a picture so I can help
It is 20 because then you will put 30 inside of 20milimeeter and put 70 years into the other pint and put it learnt into the cup
a) The change here is that metallic iron is converted into ions and copper is deposited. This is called a displacement reaction.
b)
is oxidised in this reaction.
c)$ \mathrm{Fe_{(s)}+ CuSO_{4(aq)} \rightarrow FeSO_{4(aq)} + Cu_{(s)}}$
The number of protons, neutrons and electrons an atom has determines what element it is. Hydrogen, for example, has one proton, no neutrons and one electron; the element sulfur has 16 protons, 16 neutrons and 16 electrons.