Step 1 :Given values are level of significance \(\alpha = 0.10\) and sample size \(n = 17\).
Step 2 :Calculate the degrees of freedom as \(df = n - 1 = 17 - 1 = 16\).
Step 3 :Find the critical value using the t-distribution table. The critical value is the value beyond which we would reject the null hypothesis in a left-tailed t-test.
Step 4 :The critical value is approximately \(-1.337\).
Step 5 :The rejection region for a left-tailed test is all values less than the critical value.
Step 6 :So, the rejection region is all values less than \(-1.337\).
Step 7 :Final Answer: The critical value is \(\boxed{-1.337}\). The rejection region is \(t<\boxed{-1.337}\).