A study was conducted to determine if there was a linear relationship between a person's age and their peak heart rate. Data were collected for 8 people and are listed below

Age (x) 15, 25, 30, 35, 40, 50, 45, 20

Peak Heart rate (y) 220, 190, 180, 170, 170, 160, 170, 200

a) Compute the correlation coefficient, r, and test the significance of the correlation coefficient at = 0.05?

b) From the previous part, if there is a significant linear correlation, find the equation of the regression line that summarizes this linear relationship?