-The Table Above Shows How the Number of Books Katie

$\begin{array}{|l|l|}\hline \begin{array}{l}\text { Katie's income } \\\text { (dollars per year) }\end{array} & \begin{array}{l}\text { Katie's purchases } \\\text { (books peryear) }\end{array} \\\hline 50,000 & 14 \\\hline 70,000 & 16 \\\hline 90,000 & 18 \\\hline 110,000 & 20 \\\hline\end{array}$
-The table above shows how the number of books Katie buys each year depends on her income.
a) What kind of relationship exists between Katieʹs income and the number of books she purchases?
b) Plot the relationship between Katieʹs income and the number of books she purchases in the above figure. Measure income along the vertical axis and the number of books along the horizontal axis. Be sure to label the axes.
c) What is the slope of the relationship between $50,000 and $70,000 of income?
d) What is the slope of the relationship between $90,000 and $110,000 of income?
e) Comment on the similarity or dissimilarity of your answers to parts c) and d).