In a Two-Tail Test for the Population Mean, the Null $\alpha$

Short Answer

In a two-tail test for the population mean, the null hypothesis will be rejected at the $\alpha$ level of significance if the value of the standardised test statistic z is such that: $\begin{array}{|l|l|}\hline \text { A. } & z> z_{\alpha} . \\\hline \text { B. } & z< -z_{\alpha} . \\\hline \text { C. } & -z_{\alpha}< z< z_{\alpha} . \\\hline \text { D. } & |z|> z_{\alpha / 2} . \\\hline\end{array}$