\begin{Schunk}
\begin{Sinput}
 ## Find power for a given sample size, effect size, and alpha level
 pwr.r.test(n = 30, r = .1, sig.level = .05)
\end{Sinput}
\begin{Soutput}
     approximate correlation power calculation (arctangh transformation) 

              n = 30
              r = 0.1
      sig.level = 0.05
          power = 0.08208191
    alternative = two.sided
\end{Soutput}
\end{Schunk}
