All right, now let's do this together. If d is equal to the distance driven, then to get d prime, you're taking the derivative with respect to time. So one way to think about it is, it is the rate of change of d. So we could view this as d prime is going to give you the instantaneous rate. And they are both functions of t. So one way to view d prime of two is equal to 100, that would mean, well, what is our time now? Well, that is our t, and that's in hours. So two hours, actually, let me color code it. So two hours after leaving, after leaving, Eddie drove, and this means, let me be grammatically correct, drove at an instantaneous, instantaneous, instantaneous rate of, and let me use a different color now for this part, of 100, and what are the units?