 Okay, Lydia, Lydia. I'm not sure how to pronounce that now that I think about it. Lydia, forgive me if I have it wrong. This is your sheet three, and I'm just gonna rename that model. So I'll have to remember it. And sheet one, I'm pretty sure is is B or, whoops, label these so I can remember, brand A, and sheet two, B. Okay, so here is brand A, and this is the intercept. I think I erased that by accident. This is the results of your regression when you, and it looks like you regressed it properly. You've got an intercept of 250, price of brand A coefficient of minus 0.56, and a price of brand B coefficient of plus 0.34. And I think those are right just from memory. What I'm gonna do, I am going to copy those, control C, go over here to your model, and I'm just gonna pick a place down at the bottom, control V, and I'm gonna label that B or A in the A. That's brand A data. Let's go over here to brand B. I'm gonna copy that same information, model, and I'm gonna go right there, and this is B or A in B. So now I got the information I need to construct the model up here. What we need to do in this cell that you've got 257 right now, just a raw number, we need to construct an equation that tells us how many units of sales we have based on the price of A and the price of B. And I'm gonna do that just click equal, and this is model A, so brand A, the intercept plus this coefficient times the price of A plus that coefficient times price of B. And you see now that we've got that equation in there, B27, which is that intercept, plus B28 times B8, B8 is the price of A, and you can think about that. As the price of A goes up, the sales of A go down. As the price of B goes up, the sales of A increases. So now let's do the other equation, equal that intercept plus that coefficient. Times price of brand A plus that coefficient times, it is driving me nuts here. You put this on pause because they get it to, okay, let me do that again. I'm gonna click in that cell, equal the intercept plus coefficient times price of A plus coefficient times price of B. So now we've got an equation for both of these. The equation for the sales of B, model B, says that it's 320 plus the B sales go up as the price of A goes up, and then the price of B goes up, the sales of B go down. So those are your equations. Now we just need to connect these things. The revenue equal price times unit soul. And once we get that, remember we can just copy that down and you already have that sum, so that's correct. The cost, so you've got entered in there hard coded and really that needs to be an equation again, equal the unit soul times the cost. And the same thing's true here, equal unit soul times the cost. And that should be summed down, that's okay. Now we need this to be also an equation again, and profit is nothing more than equal revenue minus cost. And that one we can copy down, and you've got that summed up correct, okay. So now we've got this 15,930 is our total profit based on this model. If the price of A is 200, then we get 59,30. If I change that to 250, you can see that everything updates. And the key thing that I did that you didn't have, when I first got here, this sale just had a hard number. And all I did was to link it, equal that total profit. Okay, that is the basis of the model that you'll use throughout the rest of this problem. And the next thing you wanna do is use the data table. Okay, now we're ready for the data table. The tricky thing about the data table is remembering what is the row cell and the column cell. What I like to do is to take those cells, go to home here, and I'm gonna say that is my row cell, and then my column cells, or remember, I'm gonna make that yellow, and that, those cells. So that helps me remember what are my row cells. I mean, my row cell is cell B8, and my column cell is B9. So to do the data table, we select that key corner cell and then highlight everything that we want from 200 to 600 vertically and 200 to 600 vertically. Horizontally. Then we go to data, what if, data table. And here is why you need to, well, I color-code those things. My row input cell is the green cell. Just gonna click on that. And I click here in the column input cell, get that blinking cursor, then I click there. And that is the data I need. And I just click that. I'm gonna go ahead and format that a bit, make this dollars. And there you go, there is your data table. So I hope this helps. I just wanna mention one thing. I'm gonna email this spreadsheet back to you so you can reverse engineer it. And remember, you can just click on a cell to look at the formula and follow that all the way through. If you double click on a cell, you can see not only the formula that's written there, but also the sales that it's dependent on. The other thing you can do is to go to, I think it is formulas, and I wanna trace dependence. I'm gonna go there, let's see if it'll, here. See there, I just clicked on it and it shows that I connected this cell to that cell. This cell is a dependent of that cell. If I go here, trace dependence, it doesn't have a formula to show that, but let's go here. I'm gonna go to that one, trace dependence. And that's a good one because you can see that the sales of A and B are both dependent upon the price of A. And if I click on the price of B, same thing is true, that the sales of A and the sales of B are dependent upon those prices and they affect the revenues which go downstream. So I'm gonna just remind you that you can see that.