Answer:
element
Explanation:
we know that helium is a pure substance although helium atoms are sometimes mixed with their isotopes it is still the same element. since there is no other element combined with helium this makes it an element.
So you need to put numbers before each compound to make sure there are the exact same number of elements on each side. If you put a 4 before NH4 there are 4 Nitrogen and now 16 hydrogen. I just played around with numbers and guessed until I got them even.
Georgia had the fewest farms.
Can there be more than one? I think there is actually 3