Can someone please help walk me through this?

We are given the hypotheses H02\": 57 Ha:,u757. with a = 0.05. If we will take a sample of size n = 18, and get a sample standard deviation of s = 8, what are the two critical 1: values (those beyond which we would reject the null) rounded to 3 decimal places? (a) left critical value: i: = C] (b) right critical value: .17: = :] Hint: Recall that the critical values are effectively the endpoints of the confidence interval around ,u instead of around it