1. **State the problem:** We need to model the temperature changes throughout the day starting at 6 a.m. with 50°F and graph the temperature based on the given rates of change.
2. **Identify time intervals and rates:**
- From 6 a.m. to 8 a.m. (2 hours), temperature rises 4°F per hour.
- From 8 a.m. to 11 a.m. (3 hours), temperature rises 2°F per hour.
- From 11 a.m. to 6 p.m. (7 hours), temperature stays steady.
- From 6 p.m. to 8 p.m. (2 hours), temperature drops 1°F per hour.
- From 8 p.m. to midnight (4 hours), temperature drops steadily to 59°F.
3. **Calculate temperatures at key times:**
- At 6 a.m.: $T=50$
- At 8 a.m.: $T=50 + 4 \times 2 = 50 + 8 = 58$
- At 11 a.m.: $T=58 + 2 \times 3 = 58 + 6 = 64$
- From 11 a.m. to 6 p.m.: temperature steady at $64$
- At 6 p.m.: $T=64$
- At 8 p.m.: $T=64 - 1 \times 2 = 64 - 2 = 62$
- From 8 p.m. to midnight (4 hours), temperature drops from 62 to 59, a total drop of 3°F over 4 hours.
4. **Find rate of temperature drop from 8 p.m. to midnight:**
$$\text{Rate} = \frac{59 - 62}{4} = \frac{-3}{4} = -0.75 \text{°F per hour}$$
5. **Write piecewise function for temperature $T(t)$ where $t$ is hours after 6 a.m.:**
$$
T(t) = \begin{cases}
50 + 4t & 0 \leq t < 2 \\
58 + 2(t-2) & 2 \leq t < 5 \\
64 & 5 \leq t < 12 \\
64 - (t-12) & 12 \leq t < 14 \\
62 - 0.75(t-14) & 14 \leq t \leq 18
\end{cases}
$$
6. **Explanation:**
- For $0 \leq t < 2$, temperature rises 4°F per hour from 50°F.
- For $2 \leq t < 5$, temperature rises 2°F per hour starting at 58°F.
- For $5 \leq t < 12$, temperature stays constant at 64°F.
- For $12 \leq t < 14$, temperature drops 1°F per hour from 64°F.
- For $14 \leq t \leq 18$, temperature drops 0.75°F per hour from 62°F to 59°F.
This function models Jack's temperature data throughout the day.
**Final answer:** The piecewise function above describes the temperature changes from 6 a.m. to midnight.
Temperature Change A841E0
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