Solve clearly

1. [4 points] MAC1= 90-3E, and MAC2= 60-2E, are marginal abatement cost functions for two firms in an industry. How should emission standards be set for these two firms so that together they produce only 40 units of emissions at the least social compliance costs? Show your work. [ Hint: Show how to reduce emissions from an industry to a target level in a cost-effective manner using standards? ]