ecial">,</span> <span class="identifier">z</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="identifier">endl</span><span class="special">;</span> <span class="comment">// to get the area for z.</span>
</pre>
<p>
            Correspondingly, we can obtain the traditional 'critical' values for
            significance levels. For the 95% confidence level, the significance level
            usually called alpha, is 0.05 = 1 - 0.95 (for a one-sided test), so we
           