What we know is that one of them is the function f, another is the first derivative of f, and then the third is the second derivative of f. And our goal is to figure out which function is which. Which one is f, which is the first derivative, and which is the second. Like always, pause this video and see if you can work through it on your own before we do it together. All right, now let's do this together. The way I'm going to tackle it is I'm going to try to sketch what we can about the derivatives of each of these graphs, or each of the functions represented by these graphs. So in this first graph here in this orange color, we can see that the slope is quite positive here, but then it becomes less and less and less positive up until this point where the slope is going to be zero, and then it becomes more and more and more and more negative. So the derivative of this curve right over here, or the function represented by this curve, it's gonna start off reasonably positive right over there.