If the experimentally determined rate law for the overall reaction is rate = k[NO]²[H₂], which step is likely the rate-determining step in the proposed mechanism?
a) Step 1: NO(g) + NO(g) → N₂O₂(g)
b) Step 2: N₂O₂(g) + H₂(g) → N₂O(g) + H₂O(g)
c) Both steps are equally rate-determining
d) None of the above