pls show all steps

3. Consider the following game with 2 players, P1 and P2 : (a) [10 points] First focus on the strategic game at the lower-right side of the game tree. Find all the Nash equilibria for this subgame, including the mixed-strategy ones. (b) [10 points] Find all the subgame perfect equilibria for the entire game, allowing for both pure and mixed strategies