$5\mathrm{.}12$ Data from the U$.$S$.$ Federal Reserve Board $($federalreserve$.$gov$/$releases$/$housedebt$/,$ retrieved April $21,2017)$ on consumer debt $($as a percentage of personal income$)$ and mortgage debt $($also as a percentage of personal income$)$ for the $10$ years from $2006$ to $2015$ are shown in the following table:a$.$ What is the value of the correlation coef fi cient for this data set? b$.$ Is it reasonable to conclude in this case that there is no strong relationship between the variables $($linear or otherwise$)?$ Use a graphical display to support your answer.