And then our y-axis, or our vertical axis, that would be the, I would assume it's in hours, so time studying. And Moussa here, he randomly selects 20 students. And so for each of those students, he sees how much caffeine they consumed and how much time they spent studying and plots them here. And so there'll be 20 data points. One, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20. He inputs these data points into a computer in order to fit a least squares regression line. And let's say the least squares regression line looks something like this.