The mortality rate of a sample of the population as a function of daily tobacco consumption can be seen below:

Number of cigarettes "x": 3 5 6 15 20

Mortality rate "y" : 0.2 0.3 0.4 0.5 0.7

With these data, solve the following:

a. Determine and interpret the correlation coefficient.

b. Find the regression line of y on x.

c. What will be the mortality rate for a consumer of 40 cigarettes per day?