Which of the following will increase the rate of a reaction?

The answers would either be b.) increase temperature and d.) add a catalyst because reactions speed up with heat while slowing down with the cold and a catalyst is a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.

I am not a teacher but I believe the answer is choice B.) hope this helps :-)

What does that mean you dum bum

Both models are effective because they show the valence electrons, and these valence electrons indicate the reactivity of an element.