But if it's the other way around, if we're draining faster at t equals three, then things are flowing into the pipe, well then the amount of water would be decreasing. So, if r of t greater than, actually let me write it this way, if r of three, when t equals three, because t is given in hour, t is measured in hours, if r of three is greater than d of three, that means water is flowing in at a higher rate than leaving. So that means that water in pipe, right then, then water in pipe increasing. And then if it's the other way around, if d of three is greater than r of three, then water in pipe decreasing. Then you're draining faster than you're putting into it. Then water in pipe decreasing. So we just have to evaluate these functions at three.