Write ionic equations for the following:
1. HNO3(aq) + NaOH(aq) → NaNO3(aq) + H2O(l)
2. HCl(aq) + KOH(aq) → KCl(aq) + H2O(l)
3. H2SO4(aq) + Mg(OH)2(aq) →MgSO4(aq) + 2H2O(l)