What has definite ratio of components

Me i dont know what to do! the table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 10 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.

What causes most sediment to wash or fall into a river

Silver reacts with oxygen to produce silver oxide. (write balanced chemical equation and identify type of chemical reaction.)