So the height right now from the bottom of the cup to this point right over here is 2 centimeters. So my question to you is, at what rate? We know the rate at which the water is flowing into the cup. We're being given a volume per time. My question to you is, right at this moment, right when we are filling our cup at 1 cubic centimeter per second, and we have exactly 2 centimeters of water in the cup, 2 centimeters deep of water in the cup, what is the rate at which the height of the water is changing? What is the rate at which this height right over here is actually changing? We know it's 2 centimeters, but how fast is it changing?