 You're already into lesson two, energy supply and demand. Energy supply and demand lesson talks more about energy resources. Basically appreciate global and national energy consumption patterns. In the past few decades, what kind of energy we have been consuming and how much we have been consuming and how we compare with the rest of the world, etc. Based on those patterns, we can also deduce some information about how much energy we use to do a job, which is called energy intensity. We will talk about that energy intensity. Based on the past pattern, predict something about the future. What kind of energy sources we would be needing and how much we would be needing based on the past trends. And we will also look at energy reserves. Do we have those if we need more coal, if we need more oil, if we need more gas? Do we have enough of those resources? If we have, it's great. If not, what do we do? Those kinds of analysis, energy analysis. So obviously you are going to see a lot of numbers and statistics. And one of the questions that I always get is, hey, do I have to remember all these numbers? You know, coal is 50% of the electricity generation in this country and natural gas accounts for another 17% or 20% from nuclear. Do we have to remember these numbers? My advice is you don't have to remember, but you get the story behind these numbers. In other words, you have to know the fact that coal is the main energy source for electricity generation. Similarly, over two thirds or 75% of our oil products or petroleum is used for transportation. So we need to know that transportation is basically run by petroleum or petroleum use is transportation. That is a fact. You don't need to remember the exact numbers. But if there is something that is very insignificant quantities or significant quantities, you might remember, for example, renewable energy sources supply less than 10% of our energy source. That is a fact. You don't need to worry about whether it is 9.2 or 9.3 or 8.5. You don't have to worry about that. So just to give you a clue, you don't have to worry about the exact numbers. But the story that is taught using these numbers is what you have to concentrate on. And we will also have one numerical type of problem in this chapter that is predicting the energy for future. That follows exponential functions, so we'll talk about that. And there will be a few numerical problems for you to practice. So after you do this, you can always do a puzzle that is attached to this over here, a crossword puzzle. And there are about 23 slides here. Discuss some questions and do a crossword puzzle. And then you can do this practice set questions. This will not be graded. It will be graded, but it will not count for your class grade. And you have some problems in your textbook. You can work those. And then you are ready to take the quiz, which counts for your grade. All right? Good luck.