In the Stackelberg equilibrium, how many goods should Firm 1 produce?

Consider a Stackelberg model with two firms, 1 and 2. Firm 1 is the leader and Firm 2 is the follower. They produce identical goods in the same market with demand function P = 65 - 2Q, where Q = q1 + q2. Furthermore, both of them have MC = 5, i.e. TCi = 5qi for i = 1, 2. Please answer question 16 - 21