Here is the presentation from today's class (one more topic left at the end): Profit Maximisation in the Long Run.
For the next class, we'll cover some new material: Efficiency in PC (please read chapter 8.6) and review previous material (check out chapters 8.3 - 8.5). It is a fairly complicated stuff, let's make sure you are comfortable with it. And as importantly, you'd know what to answer when Mr. Rod asks "what is the difference between the short and long run". (wrong answer: 5km. What is the right answer?)