What is the joint-profit maximizing outcome using the game tree in the attachment? Why is that not the outcome of of this game? Need help understanding this strategy.

Homework 5. Solve for the Stackelberg subgame-perfect Nash equilibrium for the following game tree (see below). What is the joint-profit maximizing outcome? Why is that not the outcome of this game? Leader Follower Profits Sets Output Sets Output 48 (64.9, 64.8) 180 64 Firm 2 (54.0, 72.0) 96 (32.4, 64.8) 48 (72.0, 54.0) 240 64 Firm 1 Firm 2 (57.6. 57.6) 96 (28.8, 43.2) 48 (64.8, 32.4) 360 64 Firm 2 (43.2, 28.8) 96 (0. 0)