Use A $\chi ^ { 2 }$ Test to Test the Claim That in the Given Contingency

Essay

Use a $\chi ^ { 2 }$ test to test the claim that in the given contingency table, the row variable and the column variable are independent. Tests for adverse reactions to a new drug yielded the results given in the table. At the $0.05$ significance level, test the claim that the treatment (drug or placebo) is independent of the reaction (whether or not headaches were experienced).
$\begin{array}{r|cc} & \text { Drug } & \text { Placebo } \\\hline \text { Headaches } & 11 & 7 \\\text { No headaches } & 73 & 91\end{array}$