Answer:
polyatomic, two, one
Step-by-step explanation:
you're answers are correct. Ammonium (NH4+) and Sulfate (SO4^2-) are both polyatomic ions.
If they're forming a compound then their charges have to "cancel out" in a way.
Since ammonium has a +1 charge and sulfate has a 2- charge, there will be two ammonium ions to every sulfate ion.
