I can't see the pictures clearly but maybe this will help
Haha i’m trying to do the same one i’ll make sure if i find out how too to get back to you!
No atoms are lost or made during the chemical reaction so the total mass of the products is equal to the total mass of the reactants. In an atom, protons and neutrons contribute to the mass and since the number of them doesn’t change, the mass doesn’t either.
A raised weight.
Water that is behind a dam.
Have a nice day!
