CVS Annual Reports: Return on Asset & Asset Turnover

This assignment is to compute the ratios listed below and a write a very brief summary interpreting selected profitability ratios.(Please show all calculations)
-Return on Asset: Net Income/Average Total Assets (for 2009, 2010, and 2011)

-Asset Turnover: Net Sales/Average Total Assets (for 2009, 2010, and 2011)

Company: CVS
Time Period: 2009, 2010, 2011
Source: Company Annual Reports links listed below

http://media.corporate-ir.net/media_files/IROL/99/99533/CVSCaremark2011_AR.pdf

http://media.corporate-ir.net/media_files/irol/99/99533/2010_Annual_Report.pdf

http://investors.cvscaremark.com/~/media/Files/C/CVS-IR/reports/cvs-ar-2009.pdf

Thank you!