If you have a perfectly competitive industry of 100 firms with a monthly demand curve of Q=1000-P and TC=Qi^2+100Q+100, a subsidy of $36/month, a long-run equilibrium (before subsidy) of P=140, Q=860 (each firm produces 5 units) and a long run equilibrium AFTER subsidy of P=132, Q=868 (each firm produces 4 units), how do you determine the difference in consumer surplus before and after the subsidy?
