And we are assuming that it doesn't just right get to 50 and then somehow come back down, that it will cross 50 at this time right here. And you could test that a little bit more if you want. You could try the slightly larger w, or you could see that the rate that you have more flowing in than flowing out at that time, so this r of w is going to be greater than d of w, so it means you're only going to be increasing, so you're going to cross over right at that time. So if you wanted that, want the w though, you'd solve this. Now another option, you could say, okay, we know w is going to be greater than 8, so you could say, okay, how much water do we have right at time equals 8? We figured that out in the last problem. And so you could say we, at time equals 8, we have that much, 48.544.