The following table gives the number of heart transplants performed in the Unites States each year from 2006 to 2015 (U.S. Department of Health and Human Services,optn.transplant.hrsa.gov/data/view-data-reports /national-data/, retrieved April 22, 2017):

Year ...................... Number of Heart Transplants
1 (2006) ...................... 2,193
2 .................................. 2,209
3 .................................. 2,163
4 .................................. 2,211
5 .................................. 2,332
6 .................................. 2,322
7 .................................. 2,378
8 .................................. 2,531
9 .................................. 2,655
10 (2015) ................... 2,804

a. Construct a scatterplot of these data. Describe how the number of heart transplants has changed over time from 2006 to 2015.

b. Find the equation of the least-squares line that describes the relationship between y 5 Number of heart transplants performed and x 5 Year.

c. Calculate the 10 residuals and construct a residual plot.

d. Are there any features of the residual plot that indicate that the relationship between year and number of heart transplants performed would be better described by curve rather than a line? Explain.