Page $47$: Find the t$-$table on Content of D$2$L$.$ When $=5\%,$ the $t_{\frac{}{2}}$ is found on the column of $)=(\frac{0\mathrm{.}05}{2}.$ Since degrees of freedom $($d$.$f$.)$ is $n-1$ to get a confidence interval of mean, for $n=5,=5\%,$ the critical value $t=2\mathrm{.}7764$ at d$.$f$.=4.$ Find the $t$ for a given $n$ and $.$ Do not forget to divide $$ by $2$ to find a column on the $t-$table.