Question 1158759
<font color=black size=3>
Answer: D) Reject H0 if the standardized test statistic is greater than 1.96 or less than -1.96.


We don't need to know the standard deviation as all we're worrying about are the boundaries to the rejection regions and the acceptance region. In other words, we aren't calculating the test statistic here. 


We want to know the value of k such that P(-k < Z < k) = 0.95
The 0.95 is from 1-alpha = 1-0.05 = 0.95 which is the confidence level


Using a calculator or a Z table will show k = 1.96 approximately


Because n = 40 is larger than 30, this means we can use a standard normal Z distribution to approximate the T distribution. So we won't be using the T distribution.


A way to rephrase choice D is to say "Reject H0 if the standardized test statistic is not between -1.96 and 1.96"
</font>