Now, I go into a lot more depth on things like cost functions in the economics playlist. But what I wanna think about in the calculus context is what would the derivative of this represent? What would the derivative of C with respect to Q, which could be also written as C prime of Q, what does that represent? Well, if we think about it visually, we know that we can think about the derivative as the slope of the tangent line. So for example, that's the tangent line when Q is equal to 100. So the slope of that tangent line is, you could view as C prime, or it is C prime of 100. But what is that slope telling us?