1. **State the problem:** We have data for U.S. Foodborne Botulism cases from 2001 to 2005: (2001, 39), (2002, 28), (2003, 20), (2004, 16), (2005, 18). 2. **Draw a scatter plot:** Plot each year on the x-axis and the number of cases on the y-axis. Points are (2001,39), (2002,28), (2003,20), (2004,16), (2005,18). 3. **Determine the relationship:** The cases decrease from 39 in 2001 to 16 in 2004, then slightly increase to 18 in 2005, showing a generally decreasing trend. 4. **Line of best fit:** We find the equation of the line that best fits the data using slope-intercept form $y=mx+b$. 5. **Calculate slope $m$:** Using points (2001,39) and (2005,18), $$m=\frac{18-39}{2005-2001}=\frac{-21}{4}=-5.25$$ 6. **Calculate intercept $b$:** Using point (2001,39), $$39 = -5.25 \times 2001 + b \Rightarrow b = 39 + 5.25 \times 2001$$ Calculate $b$: $$b = 39 + 5.25 \times 2001 = 39 + 10505.25 = 10544.25$$ 7. **Equation of line of best fit:** $$y = -5.25x + 10544.25$$ This line models the trend of botulism cases over the years. **Final answer:** The slope-intercept form of the line of best fit is $$y = -5.25x + 10544.25$$.