Fit Lines to Scatter Plots Practice Test

A scatter plot shows the relationship between the number of laps swum ($x$) and total time in minutes ($y$). A student drew a line of best fit.

To judge how well the line fits, which distances should you mainly look at?

A science class measured the temperature outside ($x$ in °F) and the number of cups of lemonade sold at lunch ($y$). The scatter plot points trend upward in a roughly straight pattern.

Should a straight line be a reasonable model for this relationship?