A Study Examined the Number of Trees in a Variety $$\begin{array} { l } \mathrm { R } - \mathrm { sq } = 0.886 \\\mathrm {~s} = 31394.7\end{array}$$

A study examined the number of trees in a variety of orange groves and the corresponding number of oranges that each
grove produces in a given harvest year. Linear regression was calculated and the results are below. linear regression results:
Dependent Variable: oranges
Independent Variable: trees
Sample size: 9
$$\begin{array} { l } \mathrm { R } - \mathrm { sq } = 0.886 \\\mathrm {~s} = 31394.7\end{array}$$
$\begin{array}{|l|r|r|}\hline \text { Parameter } & \text { Estimate } & \text { Std. Err. } \\\hline \text { Constant } & 390.59 & 16328.8 \\\hline \text { Trees } & 525.84 & 71.22 \\\hline\end{array}$



-Since $r ^ { 2 } \text { is not } 100 \%$
there must be other factors in influencing the number of oranges
harvested. What percentage is that and what is another factor you think might be
involved?