91Ó°ÊÓ

In Exercises \(9-12\), find the critical value \(t_{c}\) for the level of confidence c and sample sizen. 9\. \(c=0.90, n=12\)

In Exercises 27-30, find the critical values \(\chi_{R}^{2}\) and \(\chi_{L}^{2}\) for the level of confidence \(c\) and sample size \(n\). 27\. \(c=0.90, n=15\)