Assume the firm is producing 300 units when price equals $20. 300 400 MC ATC AVC What is the marginal cost of the 300th unit? (don't make this hard... look at the graph) What is the marginal revenue of the 300th unit? (what does marginal revenue mean in PC?) What are fixed costs? (hint: find average fixed costs first and then find FC) How much will profits change if the firm increases production from 300 to 400? (tough one... but you have all the info you need...)