The following table shows the annual returns (in percent) for the Vanguard Energy Fund.

Year Return

2005 44.60

2006 19.68

2007 37.00

2008 42.87

2009 38.36

a.Calculate the point estimate for.(Round your answer to 2 decimal places.)

Point estimate

b.Construct a 95% confidence interval for.(Negative value should be indicated by a minus sign.Round intermediate calculations to 4 decimal places.Round "standard deviation" value to nearest whole numberand finalanswers to 2 decimal places.)

Confidence interval_______to _________