The answer is B. This is because Sodium has 1 valence electron and Fluorine has 7 valence electrons. All elements want 8 valence electrons so they may be stale, like the noble gases are. Hope this helps.
I believe the answer is A.
Hope this helps! ^^
30% should be the percentage of oxygen if the total mass of fe2o3 is 160.
A Bronsted-Lowry acid is a chemical species that donates one or more hydrogen ions in a reaction. In contrast, a Bronsted-Lowry base accepts hydrogen ions. When it donates its proton, the acid becomes its conjugate base. A more general look at the theory is as an acid as a proton donor and a base as a proton acceptor. :)