The gas mileage of an automobile first Increases and then decreases as the speed increases. Suppose that this relationship is very regular, as shown by the following data on speed (miles per hour) and mileage (miles per gallon):
Speed 30 40 50 60 70
Mileage 24 28 30 28 24
Data Set
Make a scatterplot of mileage versus speed. Show that the correlation between speed and mileage is r = 0.

Which statement explains why the correlation is o even though
there is a strong relationship between speed and mileage?

1. Correlation does not describe curved relationships between variables, no matter how strong they are.
2. Correlation is never a measure of the strength of the relationship between two variables.
3. Since the correlation is Othere is no strong relationship between speed and mileage; the scatterplot is misleading.
4. The correlation can be 0 even if there is a strong linear relationship between the variables.
5. Correlation only measures the strength of the relationship between two variables when the units of the two variables are the same.