First, we have to calculate the mean and the standard deviation of the data,
sample mean = x-bar =39.273
sample std = s = 8.7646
Margin of error if confidence = 95%
[tex]ME=\frac{1.96\times8.7646}{\sqrt{11}}=\frac{17.1786}{\sqrt{11}}\approx5.1795[/tex]So, the answers are
Lower limit: x-bar-ME=39.273-5.1795=33.4
Upper limit:x-bar+ME=39.273+5.1795=45.2