Identify all the spectator ions in the following reaction.

2KMnO4(aq) + 10FeSO4(aq) + 8H2SO4(aq) --> K2SO4(aq) + 2MnSO4(aq) + 5Fe2(SO4)3(aq) + 8H2O(l)

The spectator ions are K+ and SO4 2-.