Now let's say things are draining out at a constant rate. If you wanted to figure out how much drains out over a certain interval of time, let's say this interval of time right over here, let's call that delta t over delta t, you would just multiply the rate over that interval of time, the rate over that interval of time, which we could represent by this orange height right over here, times the amount of time that passed by, which essentially would give you the area under the curve over that interval. The area under the curve over that interval. This area would tell you the gallons that drained over that delta t. And this doesn't just apply when you have a constant, when you have a constant rate. If your rate looked something like this, as we've seen in other videos, as we've seen in other videos, you could figure out the amount that has drained, the amount that has drained in a specific interval, let's say this interval right over here, by essentially figuring out the area under the curve over that interval. And the units work out. If you multiply gallons per minute times minute, this area is going to be in terms of gallons.