Answer:
Pb has an atomic mass of 82. If an atom of that element has an atomic mass of 80, that atom is known as: an isotope.
If I am correct it is The Third Trimester
I think it’s loss of ozone layer
Answer:
Hydrogen
Explanation:
If you combine the atoms of H2 and H5, you get 7
Gina's weight would increase or decrease, while her mass remains the same.