1. **Problem Statement:** The graph shows the relationship between temperature and time throughout the day. We need to explain what happens when the graph increases, identify time periods of increase, explain what constant parts mean, and determine if temperature is a function of time or vice versa. 2. **Understanding the Graph Increase:** When the graph increases, it means the temperature is rising as time passes. This shows a positive rate of change in temperature. 3. **Time Periods of Temperature Increase:** From the description: - From $x=2$ to $x=6$, temperature rises from about 30 to 40. - From $x=6$ to $x=10$, temperature spikes steeply from 40 to nearly 80. - From $x=18$ to near the end (24), temperature rises slightly again. 4. **Constant Temperature Periods:** Between $x=10$ and $x=14$, the temperature remains near 80. This means the temperature is stable and not changing during this time. 5. **Function Relationship:** Temperature depends on time, so temperature is a function of time. For each time value, there is exactly one temperature value. Final answers: - Increasing graph means temperature rises over time. - Temperature increases during $2\leq t \leq 6$, $6\leq t \leq 10$, and $18\leq t \leq 24$. - Constant graph means temperature stays the same. - Temperature is a function of time.