patient’s age and total cholesterol

A family doctor is interested in examining the relationship between a patient’s age and total cholesterol. He randomly selects 14 of his female patients and obtains the data presented in the scatter plot below:
Simple Linear Regression
Simple linear regression results: 
Dependent Variable: Total Cholesterol 
Independent Variable: Age 
Total Cholesterol = 151.35365 + 1.3990642 Age 
Sample size: 14 
R (correlation coefficient) = 0.7178 
R-sq = 0.5152521 
Parameter estimates: 
Parameter Estimate
Intercept 151.35365
Slope 1.3990642


a. Looking at the following scatterplot of the data, what does it tell you about the 
relationship between Age and Total Cholesterol Level?

b. Find the equation of the least squares line of regression for this data.

c. What does the correlation coefficient tell you about the relationship 
between the patient’s Age and their Total Cholesterol Level?

d. If a patient is 35, predict their Total Cholesterol Level.

e. Are you confident that predictions based on the equation of the
least squares line of regression will be quite accurate? Why or 
why not?

f. What percentage of the variation in the Total Cholesterol Level can be explained by the regression on the patient’s Age?