(a) Determine the critical values for a right-tailed test of a standard population deviation with 15 degrees of freedom at \(\alpha=0.1\) level of significance.

(b) Determine the critical values for a left-tailed test of a standard population deviation for a sample size of \(n=29\) at \(\alpha=0.01\) level of significance.

(c) Determine the critical values for a two-tailed test of a standard population deviation for a sample of size \(n=24\) at \(\alpha=0.01\) level of significance.