What is the Standard Deviation of investments A and B? Use standard deviation of population in Excel. (ex)STDEV.P Year 2006 2007 2008 2009 2010 Average Return A 12.0% 7.5% -5.0% 5.5% 13.5% 6.7% B 6.0% 5.5% 2.5% 11.5% 13.5% 7.8%