Need help. Not sure how to solve this one

Question 1: Monopoly (10 points) A monopolist supply electricity in a small town has two plants for generating electricity. The total costs of supplying electrictiy from each plant are as follows: Plant 1: TC(Q1) = 15 x Q1 Plant 2: TC(Q2) = g x Q2 + i x Q: where Q1 and Q2 are units of output in plants 1 and 2 respectively. The monopolist faces the following market demand curve: P(Q) = 40 % x Q with Q = Q1 +Q2. Find the prot maximizing quantity produced by each plant and the price charged by the monopolist