Equilibrium payoffs are (4, 5). Player A’s equilibrium strategy is “S then S if n and then N if n again.” Player B’s equilibrium strategy is “n if S and then n if S again and then s if S again.”
For(c):
Player A has four strategies:
(1) N,
(2) “S and N if n,”
(3) “S and S if n and N if n again,” or
(4) “S and S if n and S if n again.”
Player B has four strategies:
(1) “s if S,”
(2) “n if S and s if S again,”
(3) “n if S and n if S again and s if S again,” or
(4) “n if S and n if S again and n if S again.”