[tex]\bf \begin{array}{ccllll}
hours&miles\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
0&2700\\
1&2160\\
2&1620\\
3&1080\\
4&540
\end{array}[/tex]
a)
at 0hours, the plane is 2700miles away from its destination, so the plane is on a city which is 2700miles from its destination and the pilots are sipping coffee
b)
[tex]\bf slope = {{ m}}= \cfrac{rise}{run} \implies
\cfrac{{{ f(x_2)}}-{{ f(x_1)}}}{{{ x_2}}-{{ x_1}}}\impliedby
\begin{array}{llll}
average\ rate\\
of\ change
\end{array}\\\\
-------------------------------\\\\[/tex]
[tex]\bf \begin{array}{ccllll}
hours[x]&miles[f(x)]\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
0&2700\\
\boxed{1}&\boxed{2160}\\
2&1620\\
3&1080\\
\boxed{4}&\boxed{540}
\end{array} \qquad
\begin{array}{llll}
\begin{cases}
x_1=1\\
x_2=4
\end{cases}\implies \cfrac{f(4)-f(1)}{4-1}\\\\\\
\cfrac{2160-540}{4-1}
\end{array}[/tex]
c)
well, notice from b), the distance is dropping a constant value, 1 more hour, and the plane is at its destination, so the domain will be from [0, 5]
