And why does that make sense? Well, imagine a very small change in time right over here. If you have a very small change in time and if you assume that your rate is approximately constant over that very small change in time, well then your change in, let's say we're measuring the rate of change of population here, your accumulation, you could say, is going to be your rate times your change in time, which would be the area of this rectangle. And so that would be the, roughly, that would be the area under the curve over that very, very small change in time. So what we really wanna do is find the area under this curve from t equals two to t equals five. And we have seen multiple times in calculus how to express that. So the definite integral from t is equal to two to t is equal to five of this expression of e to the 1.2t minus two t dt, dt.