The Owner of a Large Apartment Complex Had an In-Ground

The owner of a large apartment complex had an in-ground swimming pool installed in an effort to increase tenant satisfaction.Nine tenants were randomly selected to complete a questionnaire that assessed their level of satisfaction with the apartment complex.Their scores before and after the installation of the pool are shown.The owner wants to assess the effectiveness of the pool in increasing tenant satisfaction. $$\begin{array} { c | c c } \begin{array} { c } \text { Tenant } \\\text { Number }\end{array} & \begin{array} { c } &\text { Level of Satisfaction Level of Satisfaction } \\\text { Before Pool }\end{array} && \begin{array} { c } \text { After Pool }\end{array} \\\hline 1 & 2 && 3 \\2 & 1 && 4 \\3 & 3 && 5 \\4 & 4 && 3 \\5 & 2 && 4 \\6 & 5 && 5 \\7 & 2 && 4 \\8 & 3 && 3 \\9 & 3 && 4\end{array}$$