1. The problem involves analyzing the behavior of the amount of coffee in the pot over time, represented by $y$ as a function of time $x$. 2. We observe that the graphs start at the origin, indicating $y=0$ when $x=0$, meaning no coffee at the start. 3. The key is to understand how $y$ changes with $x$: increasing steadily means coffee is being added, leveling off means no change, and decreasing means coffee is being removed. 4. For example, in Graph 1, the line rises steadily, then slightly decreases, then rises again, indicating coffee is added, then some removed, then added again. 5. The general formula for such problems can be considered as $y = f(x)$ where $f$ is piecewise to represent adding or removing coffee. 6. Important rules: when the slope of the graph is positive, coffee amount increases; when zero, it stays constant; when negative, it decreases. 7. Without explicit functions, we interpret the graphs qualitatively based on slope and shape. 8. Thus, the problem is about understanding the rate of change of coffee amount over time from the graph's slope and shape. Final answer: The amount of coffee $y$ changes over time $x$ according to the slope of the graph: positive slope means increasing coffee, zero slope means constant amount, negative slope means decreasing coffee.